Issues to correct if you want to use this in a plane: 1. It weighs too much. Make it thinner, eliminate all of those bolts. 2. The shaft bearing is too large and bulky. Do you even need it? The rotor is made of Teflon which has low friction so maybe it can act directly as a bushing. Might help with sealing too. 3. Maybe go back to a 3 vane design now that you've changed the mechanism. 4. Experiment with different geometries for the exhaust port to exhaust faster and reduce back pressure. The vane is on an angle, so the exhaust port can match that angle across the whole vane length to the rotor along the swept area.
Check out the type of air seals used in jet engines. labyrinth seals. Also I forget what they are called. But there's little indented rings around mortar shells. Those help trap the gas without any friction with turbulence. Of course both jets and mortars have a lot of gas so leaks are less of a worry than people think. But there might be something worth stealing because they are both incredibly low friction.
Integza, about 23 years ago as my thesis project for Mechanical Engineering Technology, my friend and I designed a 4-bar mechanism that solved this problem. We called it the QRP or Quick Return Piston, because it had a 270 degree downstroke and a 90 degree upstroke. I still have the files and paper if you are interested.
3 design changes you might want to consider: 1. At 4:15 you throttled the engine via friction by reducing the nozzle size. Instead, consider adjusting the torque demand of your propeller (diameter, pitch) if you want to trade run time against power. 2. The rod idea at 11:23 is geometrically flawed: when it is aligned with both the centre of the rotor and the centre of the hub, it needs to be the diameter of the hub. However, at all other angles (especially perpendicular to this direction), it needs to be slightly shorter, as it no longer passes through the centre of the hub. Of course, this is no longer an issue with your flap design. 3. Perhaps you could add a flexible lip to the edges of your rotor that presses against the casing - through pretension and also through air pressure.
So here we go. 1. With only 2 vanes, the engine is pulsing. 3 or 4 would increase the surface area to catch the air. 2. The ball bearing is overkill, make the case tight around the shaft. Experiment with o rings or a ledge. 3. If you're regulating the pressure to 2 bar, then you can reduce the thickness and weight of the housing. 4. Instead of vanes, you could use disks. Alot like a tesla engine just small enough to save weight. 5. Rotating mass will be your friend for extended run times due to the light weight. Attaching the propeller with a larger single bolt will help the fluctuation in rotational speed. 6. Inceasing the size of the exhaust port would allow the air to easily escape, increasing the pressure difference on the inlet which would increasing torque. All in all, a really interesting build and your build process is really relatable. Keep this series up until you battle Tom for air superiority!
@@-danR The inlet Port should be putt more into an angel. Maybe 10° more degree towards the roation and three flaps. So the Air pressure is directed to the Flaps instead of "filling" the room.
Since the flappy engine has so much less friction, have you considered going back to a three vane or four vane, that way more of the pressure that’s coming in has a smaller expansion area before the next vane kicks in, I may not be explaining this correctly but a third or fourth vane should give it more torque and or speed, just note this is an idea before the end of the video, timestamp is 18:37…never mind I just realized the total length of the video😂
Also trash the bearings, instead make the rotor with the “shaft” built in and in the main block just have a blind hole and do the same on the front cap. That drops the leak area plus with it being made from PTFE, shouldn’t be much friction!!! {-o-} diagram for example!! Love your channel, and Tomatoes are totally gross!
@@studiowilds9879the mechanical strength and low friction in bearings is almost nessesary in this situation, any other mounting will be too much friction and too weak, but if he would add a simmering to make it airtight, it would probably work better, but more flaps could maybe be a trick as you explain above
I really like the flappy engine, because it was the 1st design that moved away from traditional pneumatic air motors used in air tools for the last century. Probably due to wear rates, but still, for the intended use it's a really well thought out work around towards efficiency, power and weight.
You should consider increasing the number of flaps from 2 to 3, and either enlarge or add another exhaust port at a 120° angle to prevent compression. The operating cycle of your engine should follow these stages: inflation (at constant pressure), expansion (until atmospheric pressure is reached), and exhaust (again at constant pressure). In your current design, the expansion stage is inadequate, followed by a compression phase. This increases the overall pressure and wastes a significant amount of energy. The exhaust pressure should be equal to atmospheric pressure, so it might be worth adjusting the intake pressure accordingly. Finally, it’s advisable to resize the model to match the required output power.
Perhaps I wasn't clear enough. In the 3-flap model, the first two cycles perfectly align at 120°, and in order for the third cycle to also match, the engine would need to allow for an exhaust phase during the entire 120°. This could be achieved with a large exhaust port throughout the entire stroke, or at least two ports-one at the beginning and another at the end of those 120°. If necessary, an additional flap could be added, as more flaps increase the expansion ratio. In the 2-flap model, air is injected for 180°, and expansion occurs only for 90°, resulting in a much lower expansion. For 2 bars of pressure, a 3-flap configuration is optimal
You are absolutely right about the harmful compression. The exhaust should be at 180 + 180/flaps degrees from the input. However, it seems kind of wasteful to let that portion of the rotation do nothing. I think if he has already abandoned the use of mechanical sealing and switched to flaps, he can make the chamber oval-shaped. This way, the expansion phase can be longer than the narrowing phase, with more degrees of expansion. Theoretically, it does not make any difference, but it feels like a more gradual expansion would be better.
@@aflac82 Teflon is a brand name, it's actually just PTFE. A compound that was used in this material was carcinogenic and got banned. Your non-stick pan still has a 'teflon' coating.
Several improvements are possible: 1. Drop huge 2 psi valve and resort to using a 3D printed reed valve integrated directly in the motor. Why? Weight. You need the lightest design to successfully fly for a long flight. 2. Drop the metal bearing and simply make a PTFE centre shaft as part of your motor redesign. Both weight and less friction will result plus less leakage. 3. Your use of PTFE is great to reduce friction and also deal with engine heat, but you still need some lubricant to deal with the micro leakage. I suggest providing a amount of light synthetic oil via the central shaft where you made the bearing replacement. The centripetal force will dispurse the drop sealing not only the central shaft and lubricating it but will fly to the outside of your leafs and then seal there to provide seal plus lubrication to the leafs. You thus solve both leakage issues. On a final note, the Tesla Turbine concept which you do not mention (since it applies to fluids not gases) could draw inspiration by potentially using the exhaust gas the the outer edge to a perpendicular disc adjacent to the motor with the disc dimpled with half clam shaped dimples to catch the air but using a logarithmic sizing of reduced clam size as you work to the centre that would be exhaust port. Despite air not acting with the viscosity of liquid as Tesla design, the clam dimples could assist to additional acceleration of the central shaft of the motor. Of course such fabrication was impossible in Tesla days but with a 3D SLA printer it is. The only downside is additional weight to add this and also size since the larger diameter disc provides greater efficiency in the Tesla design. Since you wish to fly, just stick with the original 3 points. FYI - a recall around 2008 when a company out of India called Tata was proposing using air as the new fuel. They did make a prototype car but I think it only went 30km/h and so for small city driving. No clue on their engine design but I always liked the idea of air as the fuel with the exhaust as the air that went in! The question of how best to compress it likely created the additional complexity that we never saw it materialize.
1: that pressure reduction value weights 10x more than the motor itself. A reed valve sets a minimum pressure not a max. How would that work? TATA discovered that the air in India was too dirty and clogged the compressed air engine. !!
@@stephencaparelli7733 I felt so smart when he said that! Maybe I can be an aeronautical engineer after all! But in actuality, I work at IKEA, and yeah, no.
The vanes (around 5:45) are being pressed back into the core of the rotor because there's a huge pressure differential between the outside of the rotor and the inside. It's air pressure that is forcing your vanes in. When the air pressure that leaks past the vane, into the center of the rotor, and out of the engine has dropped enough, centripetal force can overcome it and the vane closes again.
It would be interesting if there was a passage in the rotor where its entry went from the pressurized zone, through the rotor, and into the bottom of the vanes' "cylinders" so that the pressure is equalized. Alternatively the centripetal force could still overpower the pressure differential if the diameter was made larger or the vanes heavier (v^2/r). Mechanical engineer here. I'd be happy to provide sketches of either!
Ditch the bearing, use straight teflon on teflon. Machine the rear housing with the shaft your rotor sits on (rotor axle and rear housing is one piece) axial drill from the back into the shaft portion, not all the way through, and then drill a radial hole on the shaft. This will be your air inlet. Now on the rotor, machine it with the propeller shaft (as one piece) then drill 2 axial holes (on the rotor) to the center in a way that times the air inlet at the correct spot in the rotation of the rotor. (rotor shaft hole placement will be tougher to time) I would suggest a taper fitments at the base of the rotor shaft, and base of the propeller shaft, this will aide with thrust sealing caused by air pressure and the thrust created by the propeller. The blow by air (should be minimal) will help reduce friction and cool the teflon on teflon bearing. Obviously, you will need matching tapers on the rotor shaft to rotor and the rotor to outside cover. This design, in theory, will reduce friction and eliminate gaps (only 3 pieces now), reducing your escape losses. The hole on hole setup (when the air inlet hole on the rotors shaft lines up with the hole in the rotor) will act as the regulator, much like that checkball on the other guys motor.
@DavidMulligan yes, but a bit more complicated. Using the air pressure to act as a cushion between the teflon pieces. Also lessens the amount of pieces, making less areas for loss.
That confused me... I'm not understanding how they were both always in contact with the outer cylinder, when they were spinning in an offset radius; was there a spring in that shaft?
@@userzero9259 it doesn't matter that it was offset, all the matters was that they stay the same distance. if you're good at visualizing, imagine focusing on just the rod. it doesn't matter what else is rotating around it, it's just getting pushed back and forth from the pivot's POV
I LOVE the childlike naiveness of youtube comment section. It's not like pneumatic engines have been practically solved for years if not decades and literally anything seen in this video isn't new nor unkown to the content creator beforehand. He's not even that good at pretending coming up with new solutions or being surprised at things like..... not using any lubricant, LMAO.
Use less diameter bearings to reduce the area of leakage in them. Also, it's better to have more volume of the engine cuz it improves the ratio volume/leakage.
I believe if you have more volume in the engine the running time will lower because air in the bottle is still the same so % of air that is wasted is higher
Or 0 ball bearings, since it only runs for a couple minutes he could just use teflon sleeve bearings/bushings with some light oil or grease. Also if he was to change the drive shaft to steel he could use a much smaller diameter which would result in lower leakage around the output.
A way to eliminate some of the leakage as seen at 12:40 can be using sealed/shielded ball bearings or even better, fluid shield bearings! not only it'll eliminate the bearing leaks, it'll help the engine run smoother since the bearings are constantly lubricated.
From what I'm seeing, you're putting more air through the stuff and never letting it out, that's why you get leaks. There are 2 chambers separated by the vanes. The first one gets the air intake and it's volume grows, that's fine. The second one has a somewhat constant air quantity, but it's volume shrinks, it builds up pressure, resists the movement and ultimately generates the leaks. Add an outlet hole in this chamber. If i'm right you might get a better seal, and less resistance from the outlet chamber.
My background is industrial maintenance. My recommendations are simple. 1: Enlarge the end of the housing to accommodate a lip seal on the shaft. 2: Put the on/off valve between the pressure regulator and the motor. Air flow does act funny sometimes. 3: Enlarge the housing to a pill shape and supply air to the second chamber. You may have to reduce the size of the restricted orifice going into the motor. Just some ideas.
As an engineer I've seen something similar in a marine application here's what I suggest. Use a 4° reverse vein use your pushrod design. Use graphite powder dry for a lubricant and gap filler. Your central peace should be two parts to clamshell against the veins and the pushrod unless you can get tight fitting as single piece. You may even be able to go to a three vein 2° reverse angle using a cam style to move the pins in a direction to keep the veins close to the outer shell. And you could then use a nitrite seal or similar automotive style seal on the output shafts of your rotary vein. That would minimize your parts your escape portions if you do the tight tolerance thing again with the seal it would keep everything much tighter with less friction minimizing your parts and less air gap
The 2-part clamshell to get a tight fit around the sliding vanes is a good idea in theory. But that gap is already eliminated by being the solid attachment point of the flaps.
This is awesome. I love this little flappy engine; I think you have landed on what could be the new gold standard design. Please check the sealing on the piston's axial direction. If you machine annular flap seals into both piston faces, remember that the propeller is pulling the piston towards the front, so the seals on the back face of the piston will have more clearance. For even better sealing and less friction, you could make the entire expansion chamber PTFE, using the resin housing for structural support. Or just machine a grove in the housings for PTFE o-rings. Finally, your bearing isn't the best one for an airplane. You need a thrust bearing in the front of the engine and a sealed bearing on the rear. The front bearing and engine housing is taking all the load of pulling the airplane forward.
Quick, simple, and requiring no major container changes: Increase the number of flaps. I KNOW you reduced the VANES to 2 to reduce leakage; however, flaps are different because the pressure increases the seal. Thus, more vanes means more torque AND without sacrificng sealing. NOTE: I am NOT suggesting going from 2 to 3; rather I AM suggesting seeking a sweet spot which might be 3,4,5, etc. to find the optimum between the net increase in friction with the net decrease in leakage. You MAY need to simultaneously seek a sweet spot with regard to pressure as well. Hope this helps. BTW, I love your presentation style.
i think it very much depends on how much friction each vane/flap causes, if there are two pressurised cavities (implying 3 vanes/flaps under some pressure) then the mid vane has pressure on both sides, albeit that the pressure in the cavity nearer the inlet ought to be greater than the cavity about to exhaust.
It's not that simple. If you have too many the airflow into the chamber gets cut off too soon. Most energy is probably extracted between 30 and 60 degrees after the inlet. With two flaps the movement after 60 is not helping much. With four or more you are not maintaining full supply pressure throughout the productive part of the cycle. It could be calculated more rigorously but my gut feeling is that 3 may be the optimum. You are right, his reason for moving to 2 has gone, he need more flaps.
@@nomdefamille4807 Thank you for your well considered response. In my mind I pictured sort of a water wheel -- but you may well be correct. I am not much of an engineer; I have always taken the million monkeys approach -- admittedly, more tortoise than hare; but it usually works in the end.😀
@@nomdefamille4807 Thank you for your insight. You are obviously a much better engineer than old kitchen chemist me. I had visions of a sort of water wheel efffect; but, that just might be the amateur in me. I still think something along those lines might be worth a shot. Who knows; even if it fails, it just might provide some iterative inspiration. 😀
@@tuberroot1112 FYI Commercial vane motors can have up to 10 vanes. It appears to be a judgement about lower friction vs lower internal leakage and RPM. As long as the vane still has space to expand outwards then the air can continue to expand. Given the inner rotor is offset from the outer, the rotor can rotate 180º and continue to expand.
I just randomly happened to have this video pop up. I know nothing about air engines. But, this comment section, which I see as a super nerdathon... Is probably one of the coolest things ever, seeing everyone providing so much help towards creating perfection. I wish I could be like all of you.
Man, this air rotary engine idea is crazy! Imagine using a nautilus spiral for the chambers resulting in smooth airflow, less turbulence, and max efficiency. Pair that with interlocking rotors, kinda like layers in a satellite design, and you’ve got continuous compression with almost no stress on individual parts. Oh, and dynamic balancing? Add some flywheels or counterweights to keep it running steady even at high RPMs. You could even go modular by stacking rotary layers like pancakes for more power and redundancy. And instead of just air, tweak the design for steam or gas mixtures too. Ducted pathways with adjustable vanes? Boom, variable compression ratios on the fly. Seal everything tight with optimized D:d ratios for minimal air leakage. This thing could integrate planetary gears straight to a generator or drivetrain, no problem. Test it out in CAD first to get those nautilus chambers airflow-optimized. Legit hybrid engine potential here!
I think you should add a gear train to the engine. Also a teardrop exhaust port would probably help exhaust pressure to increase overall preference. You could use a seal or an o-ring around the shaft to prevent loss of air pressure.
@@orestdubay6508 Yep my 50 year old marine engine used a vane cooling-water pump with "compliant" rubber impeller, It's a far older design than you think. Making it low friction is the challenge here though.
Given the friction, what about making the flaps replaceable tabs that lock in with a key fit, but doesn’t add extra leaks? After enough run time the flaps would wear down like apex seals do.
Given the leakage occurs through the bearing, the bearing itself could be extracted from the main piece. It would be kept aligned to the rotation center axis, but only sustaining a center rod with minimal radius to be sealed against the pressure chamber.
5:30 Van is sucked back to center because the chambers are expanding, but the inlet is blocked by the next van. The air tends to move from high pressure area(the chanmber just finished filling air) to low pressure area(the expanding chamber on the right). This design is not air tight at all so there will be tremendous air flow between the chambers. The van is moving out due to centrifugal forces, which also created a low pressure area near the center of bearing. All above is just my personal analysis, hope this can explain something to you.
Simply fantastic work! The pressure regulator acts like a restriction in the feeding line. The pressure drop is wasted energy (deltaP X Flow). You can compensate the pressure variation (and, thus, torque) changing the excentricity of the engine Higher the excentricity, higher the torque for the same air pressure. Note that, initially, when you have higher pressure,you will need a smaller excentricity to generate the needed torque. Lower excentricity leads to lower flow, thus reducing compressed air consumption. When the air pressure is low, at the end, the excentricity is increased, sustaining the needed torque for longer. This can be achieved with a movable engine housing, actuated by the inlet pressure Look for "variable displacement vane pump" Greetings from Brazil
Yeah, I noticed the waste of energy in the pressure regulator as well. You reduce the pressure, but the amount of air molecules that are in the bottles and can go into the engine stays the same. But wouldn't an engine with zero eccentricity waste air molecules instead? Yes, you get less force, but the air coming into the chamber is still 2 bars (or actually even more), and the "input cutoff size" of the chamber (the size at the point when the input port gets cut off) is basically identical to the "input cutoff size" at maximum eccentricity. And any time the chamber reaches the exit port, the pressure in it is still dumped from X bars above ambient to ambient pressure, even with zero eccentricity. I have a feeling that variable *eccentricity* only works for pumps. For engines, you probably want to keep *maximum eccentricity at all times,* but "vary the position of the input port". With high pressure, you want to input port right next to the "apex" (where the rotor touches the housing), since the chamber is smallest there. But for lower pressures you'll want the input port moved to (or a secondary input port opened at) 90° from that position, where the volume change of the chamber is highest. And obviously, varying the position of the input port with respect to the point where the rotor touches the housing can also be achieved by shifting the rotor axis, so that the point where it touches the housing moves with respect to the (fixed) input port.
I LOVE LOVE LOVE that you took on this challenge. The pneumatic engine removes combustion dangers, allowing everyone to try new ideas on one of the most useful components of the modern world. Converting stored energy into mechanical rotational energy. Years could be spent tinkering with pneumatic engine designs. Its incredible the varied possibilities that exist, things that have never been thought up just waiting to be discovered. My favorite video EVER that you've created. Except needs more exploding "Tom"atoes.
The whole point of a tesla turbine is to blow air directly on a set of discs, so unless you mean "scrap everything you were doing to make a Tesla Turbine instead", the mechanism he's using inside is taking up the exact spot he needs to make a turbine with.
Brilliant video! My 2c below in 10 points. Difficult to put into text but I'd love to be able to discuss further. So much to elaborate on. 1) Balancing: Kind of speaks for itself, but balancing anything that has rotational forces is a great start. I wont waste text on this point. 2) Number of vanes: I would go back to 3 vanes min. Doing so would reduce weight and also allowany of the following ideas to be beneficial. 3) Vane and running surface shape: Make the vanes rounded at their ends where they meet the bearing surfaces and as such the outer walls/extreme running surfaces should also be curved to match. Hydro dynamics tell us that square edges only create drag. 4) Bearings: Perhaps try a "mag lev bearing" like the ones used in "Sunon" computer fans to reduce friction. 5) Sealing: A micro fillament material or even something such as lambs wool which is self lubricating, heat resistant and waterproof (so it won't wick moisture from the compressed air which would cause excessive friction) for the vanes along the outer edges which contact the outer running surface and side walls. 6) Weight: Will likely increase with above proposed bearing however rotational mass lends inertia which will also increase lending to use of different propellers. 7) Propellers: Propellers are potentially the most interesting part of this application and depending on the size, shape and purpose of the machine you wish to propel, will have possibly the greatest significance. Going into this in one (already too long) comment isn't possible. 8) Power run/pressure side: Shorten the length of the power run but add vanes and make the chamber a "snail shell" design so that the maximum pressure of the chamber becomes more constant. Ie. Larger at the initial point of pressure, reducing in size towards the end of the power "stroke" so the increase in volume of the chamber doesn't expand so quickly and drop off before the next vane picks up the new power run. 9) Porting: Soooo much to do here! Rather than trying to eliminate pressure leakage entirely why not try manage/redirect it? First play with port angles and shapes of both intake and exhaust. You could create a gradual exhaust port using a contracting slot in the outer wall/running surface being max open at the start of the exhaust run coinciding with the start of the following vanes power run. This port would reduce to zero at the end of the exhaust run just BEFORE the leading vane begins it's power stroke/run. By doing it just before, I'm hoping you might be able to create a slight negative pressure to help the vanes slip easier using air as the lubricant in the micro fillament (or lambs wool). But...! EVEN BETTER than both of these would be "NO MOVING PARTS PORT TIMING" by using a tube entering the outer wall at an angle so as to create an oval shape (the fixed shape of which could be altered by the angle at which it enters the inside wall) would essentially gradually open and close an exhaust port as the vane passes over it with the angle at which the tube enters changing the shape of the port. The "timing" part comes in as you can then route the exhaust back to the pressure/power side wherever it is now greater than the initial pressure of the vane on the current power run accepting losses on the system due to sealing issues. Routing this exhaust via a seperate run gives the ability to recycle much of the pressure and have it enter at a given point to add pressure to the power chamber and keep the pressure more constant as it expands with the passing of the vane whilst it moves along its power run. Playing with the shape of this exhaust chamber and timing its relief (via expansion rate) and then adequate compression rate for the next stroke via compression would be very interesting indeed and much like using a 2stroke expansion chamber which on a highly technical level, I'm sure even the acoustics would have an effect (and if by some miraculous means your project somehow gets to this stage... Best to send it off to Yamaha me thinks... Those who know, truly know). If you had the tech available, this exhaust route could be made of a UHWMPE microfibre to keep weight way down but when pressurised would maintain a constant shape. The density of the weave on such a fabric could even allow the ability to bleed off unwanted pressure for a given application. Alternatively, porting could even be used to run exhaust or initial pressure through a central turbine fan shape if the central bearing allows through-passage. 10) Friction: Eliminating friction as soon as possible after the exhaust run may also be possible by removing as much of the walls and/or outer running surface after the exhaust run also helping weight reduction of the unit without affecting the rotational mass needed for enertia. I'd love to try designing something like this and see the effect of each stage. A 3D printer would definitely help... Just saying 😁
Hello, in order to reduce leaks between the transparent plate and the rotor, you could install a series of 2 or 3 baffles, they are used in applications with very high rotation speed and high pressure. I remember this passage from my engineering classes. With the tolerances of your printer this might be possible. (sorry my english is bad it's not my native language) Edit : There is no friction with this solution, because the two parts do not touch.
I was thinking some matched up oil grooves for the same leakage points. since it's a short duration doesn't matter much but needs sealed. and a frigging o ring around the main body and clear plate. once the spinny bits are better sealed, that body is going to be the next spot.
The pain of air engines...it's so addicting hah! Best way to reduce friction of the rotor further is to reduce contact area against the housing faces. So just have a small lip around the whole edge (plus the whole flap of course). Less area means less friction so you can have a tighter fit for less air loss and same friction. Or same air leakage with less friction. Really clever design, how long do those flaps last before fatigue failure?
Contact area isnt really important for friction. You have to reduce the normal force and the coefficent of friction. With the rotor fixed on the ball bearing and effectivly flying in the housing,giving the rotor - housing clearance a thight fit, you could increase the almost contact area there and smear it with thick grease to seal it.
@@AA-rc6ob Should be less. Any point of contact is an opportunity for leakage. The force at any point of contact is directly proportional to the pressure - it doesn't matter how large of an area there is. However, the amount that manages to sneak through per area also depends on the pressure, so if there's more area, there's more total flow through that area. This is why his smaller nozzle provides longer runtime but less torque - it's the same force coming out per area of the nozzle but there's less area so less total flow.
It took me nearly 30 years to finally enjoy the taste/texture/nutritional content of tomato. I first started enjoying them when I grew a cherry/grape tomato plant on the patio called "Sun gold" Their taste is very good, especially right off the plant warmed by the sun.
Yeah he went dual veins because of sealing and springs and kept it as he went to flaps but with the flap designs there is no reason to keep only two veins. Not sure if more veins will help getting better results but it should be tested for sure.
@@gg4760-k5n Three vanes will probably help, because as-is air inflow can leak over the back of the rotor to reach the exhaust and lose pressure. Three sections will allow a filling section, a power section, and an exhausting section.
more longer, thinner flaps makes for turbine, but that'd be heavier and brittle - engine that works till first touchdown? 2. Do we really need to sal friction of teflon against teflon? Doubt.
Hi Integza, Phi here! I have a bit of experience with vane motors and vacuums pumps. It looks to me like you can solve a bit of your tolerance problems by making your rotor larger, and the vanes shorter, in your flappy motor design. It will give them less opportunity to flex under the air pressure, and allow for you to run it faster or at least more efficiently. For the vane design on the other, narrower vanes are better, but the cavities should be sized such that there are extremely tight tolerances, and when the vane is fully extended there should be about 2/3 of the vane left in the gland, otherwise friction will try to drag it out of its space, causing more friction, and eventually self destruction. Gaskets and rotary shaft seals are grand!!! Three vanes are better than two in all regards. Cheers!!!
Great video. Using a pressure regulator adds weight. Try using an adjustable throttle valve instead of fixed diameter aperture. It also makes experimenting and testing a lot easier. To save on weight, instead of trying to fit Your engine to the plane, build the engine so it attaches directly to 2L bottle. Let the bottle become the fuselage and just add wings and stabilizers to it.
If you also put the flappy flap on the side the engine would have an even better seal. Also, test again with 3 or more flapy's at a lower pressure. Maybe you can increase the runtime even longer.
Greetings inventor, I am Lucas Freitas, I am an engineering student from Brazil, recommendation for the upgrade: 1 Use sealing rings on the fitting parts 2 Add shielded bearings 3 Use car cylinder head sealing glue around the mechanism; All this will help keep the air where it should be Otherwise the engine is very good. I hope it helps you based on previous experiences
My favourite video of yours. It's just one good idea after the other. Good luck kicking Tom Stanton's 🍅 Quickest/easiest fixes: 1. 3D-printed flap mechanism + teflon housing. CNC cutouts around flaps increase the volume of air wasted. Maximize pressure differential vs volume per compartment. 2. Print versions with different amounts of flaps. Finding the correct amount in theory will take forever. Just print versions with 2 up to 5(?) flaps and see what's most efficient. No math needed. 3. Use a liquid, plastic-compliant lubricant. It's basically a free sealing agent. 4. Ball bearing in the center really makes air leakage too easy. Teflon center shaft and a lubed bushing would have just as little friction and be much easier to seal. 5. The front and back wall need to keep the air in the flap compartments. Look up a "labyrinth seal". Perfect for rotating designs, easy to implement, basically zero friction. Add the lubricant, boom, got a great seal. 6. Where is your outlet? It wasn't entirely clear in the video. Just make sure the air escapes quickly after the halfway point, otherwise the engine is working against itself. 7. Housing with a nautilus shell shape, but with a very smooth transition, so it doesn't wreck the flaps or cause them to catch. Then you can use almost the full rotation for expansion. Adjust outlet position accordingly. 8. Make sure the back wall is stiff enough to make the deformation due to axial force from the prop negligible. Otherwise sealing the flaps will be even harder. Those are all the easy ones I can think of. Edit because I was being dumb.
Flappy engine was a massive improvement. I am a little surprised that you did not make the flaps in a way to push against all walls. not just one. Super fun video! Thanks for creating an amazing content.
Please make a version 2 of your turbo jet engine that will run for longer , it was one of ur best videos, I too felt the joy when it started working , plsss.
I know I'm too old for a Make-A-Wish, but I hope fate lets us hangout within the next 18-24 months. Making a project with you is definitely on my bucket list. You seem like a genuine and funny person. Both of which I could really use right now.
Armchair Design Ideas: 1. Increase the number of vanes to at least 3 to ensure at least one is always producing torque. 2. Progressively port the exhaust (teardrop shaped passage in the back housing) so excess backpressure can begin to vent as soon as that flap's specific trapped volume begins to decrease. 3. Buy a one-side sealed bearing so air can't leak through the ball race. 4. Clamp and glue the case instead of screwing to reduce mass (design in alignment tabs). 5. Build a small sliding-spool pressure regulator into the inlet because the one used for testing is entirely too heavy to fly. 6. Make the rotor wider (deeper?) and the vanes shorter so the conformal hinge doesn't have to flex as much, and your average moment arm will be longer. 7. And the crazy one: Commercial pneumatic vane motors sometimes use inlet air pressure to load the vanes against the walls instead of springs. The air is ported through the housing, into the rotor, and delivered into the rear of the vane cavity. Big advantage because the friction is directly related to supply pressure, meaning at light loads, you will have less parasitic loss. This might not work with flaps normally, but... since you have a resin printer, what if you modeled a Bourdon tube (like a pressure gauge or a party blower) into the vane to act as the spring?
What especially kept me on this video was the detailed explanation of the occuring flaws of your engine. The light nagging to tom, the 'ping' of cutting the spring at 6:05, the 'farting' engine at 11:05 are the small things, that are the cherry on top to me.
@integza 11:23 axis isn't in the center, so when it is perpendicular to the vector of change (I hope you understand) ends of the rod touches 2 sides of the circle, but when it is parallel to the vector the distance between end 1 and end 2 is a diameter, what basically means the rod is too short. summarizing, springs were better
Use a tight fitting teflon/nylon bushing instead of a ball-bearing. You get a better seal and lower weight. Downside is it wears out faster, higher friction loss until it wears-in. Pack teflon tape around the crankcase cover for better sealing. Use powdered graphite lubricant instead of a liquid. Less fluid drag and it eventually builds up to form a seal. You can probably swap out the metal bolts for polymer ones to get the weight down. Every gram counts.
To improve this wonderful tiny thing: 1. Center the air intake as much as possible for the airflow to hit the flaps (it's not about max torque, but about the air efficiently pushing them) 2. Make the flaps into a pelton turbine shape: if it's efficient for water, it's probably great for air too! 3. Get a bearing with a rubber side: a lot of pain was leaking through the bearing! 4. as @naasking was saying, experiment with 3-flap design and try to reduce back pressure 5. find the optimal width: with eiter software or a couple of prototypes, surely there is an optimal width that maximizes torque without killing rpm. I hope this helps! Much love from Italy!
the traditional pelton wheel gets its advantage over the venerable water wheel by providing a course for the fluid to reverse direction in to an "unconfined space", so for that aspect the air needs to leak out. here i think he needs the torque of the "rotary piston". if he is currently running for 3 minutes against a need for 2 then he could open up the inlet nozzle slightly and increase the depth of the rotor/ motor. he really should try and dump the regulator, the assembly would better use the stored energy if it could withstand peak soda bottle pressure. and in terms of flight performance anything to reduce weight, as all others have pointed out.
@@dziubo1 I suggest you go and have a conversation with Mr Bernoulli and ask him to explain his gas principle to you, then you might be able to answer your own question.
add a ball valve before injection, reduce chamber size, make a spiral to open and close the ball valve only when you need it for the amount of air needed to achieve the rotation you need.
It would be so awesome to see a collab! First, one video that pits you both against each other facing an engineering problem, then another video in which, together, you both integrate the best of each design to produce the best possible solution! INNOVATION MUST COME NOT ONLY FROM COMPETITION, BUT ALSO FROM TEAMWORK!
Suggestions: Try using a low viscosity vacuum oil to help seal leaks. Cut a tiny flap at the edges of your rotor to help seal at the acrylic front and rear, like you did when replacing the vanes. Use a very small food grade sealed ceramic bearing to eliminate leaks through said bearing. Try cutting a deep groove/slope just before the flaps, towards the center of your rotor so you can make the flaps much longer and improve your F=P*A ratio.
18:32 I would think that combining your flap design with your vane design would be best. Like a vane that has a flap sticking out of it, like a y ... you also might consider an o-ring seal around the core of the rotor, against the walls of the chamber. to prevent air from leaking that direction.
To improve: make side-flappies on the flappies and the rotor body to eliminate leakage against the flat surface of the housing body. Play around with angle and position of the entrance. I have a gut feeling that says you will get better yield at 5° further and slightly steeper stream angle (which now is perpendicular). And perhaps bring back the 3rd flap. Also, adding a second exhaust hole where the inlet no longer feeds the cavity, will reduce friction in the second half of the rotation...
Lets call them micro flaps (on the sides of the flaps). Why not have a slit for the exhaust (about 1/3 or 1/4 the width of the flap) extending around the back half of the motor for about 170 degrees (just under 1/2). No idea if these will help but they are ideas to try.
So many good comments already... I think you could increase efficiency by limiting how much the lips need to deflect (loose energy in deformation) but that is probably minimal. The exact angle for the intake and outage round your motor should be planned properly also to make sure that air is expelled at wanted pressure outside the chamber (basically 1bar)
Just make sure that when you're making the plane it's built more like a glider, so it's easier for you to keep it in the air even when the air pressure drops
When I buy any 'cheap' air tool, I run it for a baseline, then tear it down and check everything using a granite surface plate and Prussian Blue. Once all the parts fit, lapped, sharp edges chamfered, orientations to ports corrected, that cheap $20 tool will almost always perform like an expensive brand name tool. Love your flappy design and your follower vane, I can see real world applications in my future.
I enjoy how you trouble shoot through the issues, great to watch. To try fine tune your flappy engine, now that you have resolved your leaking issues, maybe reverting back to more flaps now. I would assume it would work on the same concept as a two stroke engine and a four stroke engine… produce more torque at lower rpm, generally have better durability than high-revving two-stroke engines and also provide improved fuel efficiency. 🤷🏼♂️ I’m no engineer but love trying to figure out how to make things better.
Grease will slow the whole movement. Low friction and light parts use very runny oils for lubrication. (if you drop a small screw into a blow of grease, it wont roll out of it anymore) The slower or heavier the movement, the thicker the lubrication gets. Using teflon as material eliminates the need of lubrication.
Grease (plumbers being one of hundreds of types and proporties) will act as a small liquid gasket sealing any tiny air gaps. Teflon may be friction free, but you still can't machine Teflon to run with no air gaps and expect it to be free moving. There are some greases that thin out when heat builds up, and although this air rotary design is only air, the compression then expansion of the air, through the motor, will generate a small amount of heat. Plumbers grease will thin out slightly with the heat yet still provide a reasonable seal. If not plumbers grease, there will be a grease that will be perfect, but it needs researching properly.
The blue liquid he pumped in showing the leaks is a good example. Imagine the liquid he pumped in smearing all around the front window of the motor. There's your liquid gasket. Or one huge liquid rubber washer so to speak.
16:43 adding a pressure regulator will make the engine run for longer but you are also adding more weight again. You're going to come to a point where you got your engine design perfect and then realize it still won't fly because it weighs too much
3D print a seal on the ball bearing, similar to a sealed bearing (or try a sealed bearing?). I suspect that reducing this source of air leakage will help. Also try adding oil into the chamber before you screw on the cover, instead of just pouring oil through the bearing. This oil may help take up some of the tolerances.
Ideas to Improve Your Design: 1. For sealing: I would modify the rotor design so that its sides are flat with grooves for rings. These grooves should be slightly off-center with respect to the axis on each side. The blades should be positioned in the center between the flat faces of the rotor or between both groups of rings. Part of the blades should be cylindrical, located approximately near the rotor's center, where I would place rings to prevent leaks from the blades. I would also add seals to the rotor shaft where the bearings are located. 2. To enhance performance: I would utilize the Venturi effect to create suction at the exhaust by using pressurized air at the intake. This would improve both performance and efficiency. I also have ideas for the lubrication system. 👍💡
If you notice, the two engine models are inversions of common compressor types. The first one resembles the piston-type compressor, and the current one is rotational. However, there is still another type to consider: the rotary screw compressor. Perhaps, by applying compressed air to a lightweight resin-printed, adjusted version of this type of compressor, rotational motion could be achieved more effectively, as the rotary screw design is the most efficient of the three. Only check the friction and leaks of air
Hey there! I just watched your latest video on the compressed air engine, and I have a few thoughts and suggestions. First off, you removed one vane, leaving only two, and replaced them with those floppy things. Remember, as you mentioned before, more vanes generally mean higher RPM and power. So, have you considered adding more floppy things instead? Speaking of improvements, why not try lubricating the engine with graphite? It worked well for the rotary engine in your previous video, so it might be worth a shot here too. During the leakage test, I couldn't help but notice some noticeable leakage around the bearings. That might be something to look into. I'm a bit curious about your end goal here. If you're aiming for maximum flight time, the two-bar setup might be sufficient. However, if I were in your shoes, I'd consider increasing the pressure up to 2.5 bar for better power output. Lastly, when you eventually get this contraption airborne, I wonder if the pressure regulator might be too heavy for successful lift-off. Have you considered its weight impact? Keep up the fascinating work! I'm looking forward to seeing how this project develops.👍
Yeah I know, but I'm not English. I'm just shit at writing in English. It's also not necessary I mean no one will ever read this besides you. So yeah the translator does the thing for me.
The flaps could be made more robust as a pivoting hinge (it would probably introduce another leakage point, but might be worth a try). The hinge would just be a cylinder embedded in the circle. From the top, the hinge would look like a comma, with the circle part of the comma inserted into a corresponding round cavity in the rotating circle.
That air flap at around the 14 minute mark was freakin genius! I was thinking about wankel engines and how the apex seals work, trying to figure out how to redirect that rouge air and you did that, fantastic!
You should check out the Di Pietro Rotary Air Engine. It operates on a principle similar to the pneumatic vane motor, with greater efficiency but can be harder to manufacture,
"Hey Integza! I absolutely love the concept of your air engine, and I have a suggestion to improve its efficiency. What if we try using curved blades instead of straight ones? Curved blades, similar to those used in wind turbines, can capture more air and reduce drag, potentially improving the engine's performance. Additionally, if you used carbon fiber for the blades and housing, it would be lightweight and strong, which could reduce friction and make the system more responsive. Lastly, how about adding a pressure regulator to control the air intake more precisely? This could help manage energy better and improve the consistency of the engine's output!"
Add a casing around the motor and connect the intake to the space between the motor and the casing. This space will then be pressurized, preventing air from leaking out of the motor. It is particularly important to ensure that the shaft penetration is properly sealed.
Hi! Cool stuff, i admire Your process! I have one comment - it's not so intuitive, if You're used to electrical motors, but air engine like this consumes more air when running without load! So when You adjust the nozzle to make the engine run for 1 Minute as initial design, propeller should be installed. But it doesn't change that Your leakage optimization is very cool and would have been necessary anyway to get this overall efficiency. Maybe in a future project You can build fitting lightweight tiny proportional valve to control the rpm of Your plane, instead of this fixed nozzle ❤😅 This would also increase the flight time when You lower the power and glide 😊 Anything You'll do will be fun to watch anyways 😅
oooo an engine that works via compliant mechanisms, that's fun! Biggest issue I see is that you probably have quite a bit of wear on this engine, even with such a low coefficient of friction, right? As long as it runs, it runs great, but eventually the pieces will wear down so much, you get too much leakage again, I think. With the flexure version you *could* try going for a three-finned variant again. Might be even better? Though two-finned seems to work rather well
To increase durability, you can make the flaps longer. Right now it looks like they are just about the ideal length for maximum leverage without leaks, but when they wear down it will very quickly start leaking since the flaps won't reach the edge anymore. So for a more long term engine, I would add maybe 2mm of length, slightly decreases efficiency but makes it much more reliable over time.
by making the flaps longer you gain a certain amount of built-in wear resistance the flaps may wear down, but they have to grind through the whole extra length of the flap....
@@Kram1032 as long as they aren't so long that the cross section of material touching the wall increases, it shouldn't be much more. however, if the flap is too long or thin then then it will overcome the strength of the teflon, sag and drag excessively along the wall
You should make an radial lip seal that closes in the axial direction towards the bearing as part of the front of the transparent housing behind the bearing. Or an axial shaft seal. .
1) Optimize Air Intake Quality: Ensure the air entering the engine is clean and dry. Contaminants can increase wear and reduce efficiency. Implementing effective filtration systems can help maintain air quality. 2)Refine Flap Design: Possibly making them like an aerofoil like a propeller would to help efficient movement of air, rather than just a flat wall. An increasing it back to three would help regulate even pressure better (i guess more like a capacitor discharging to allow smoother flow of electricity). 3)Alternative Materials: Consider materials like graphite composites or ceramics, which offer excellent low-friction properties and higher wear resistance. Maybe make the bearings ceramic? and coat the chamber in a graphite composite. 4) Heat resistant coatings? Maybe leakage increases over time as temperature rises inside causing expansion between parts. Possibly the use of gaskets would help. Really enjoyed this video, that was recommended to me. You have yourself a new subscriber
Absolutely love watching you develop these! Couple thoughts I had: 1. Are you still using some lube with Teflon? Can't hurt right? 2. I think the compression/pressure goes down with travel. So, I think going back to more flaps would be better. Would love to know if this works! Tomatoes are disgusting!
If you keep if named flappy valve it should probably resemble flappy bird! Could you replace the vane system with a compliant mechanism? For optimization: I think you can change the expansion chamber to be more round and have a better flow profile. Second, you could adjust the volume of the expansion chamber. Third, adjust the amount of flaps. Optimizing these could produce a higher rpm and longer run time.
Nice idea! Have a back half and a front half. Front half would just be a front bearing and crankshaft to the propeller. Connect the two rotating parts via magnets. The issue would be you'ld want strong enough magnets to keep the parts connected but not so strong they tried to clamp together causing friction.
I want to say no, that won't work but I can't think of any reason it wouldn't that couldn't be overcome with some clever design. At least for very low power applications like this. Yeah, I can think of several things that would prevent the motor working but they are all things that could be solved easily. Nice idea.
I gotta say, that was a super creative way to approach that problem. I’m curious how well the flaps would handle bending fatigue over time but overall really ingenious.
you could probably get more rpm if you added a few more flaps and measure at what point the amount of friction from more flaps decreases the efficiency. Great idea though and beautifull you made it work.
Get an exclusive 15% discount on Saily data plans! Use code Integza at checkout. Download Saily or go to saily.com/integza
Yes bro ❤❤
Thank you❤
PLEASE MAKE A ROCKET TURBOPUMP!!!!!!!!!!
PLEASE MAKE A ROCKET TURBOPUMP!!!!!!!!!!
PLEASE MAKE A ROCKET TURBOPUMP!!!!!!!!!!
Let me know when you get it flying 😉
Would love to see an in-person competition between you two ;)
He can't get it to fly
Do a competition for a video
He have all types of engine in the world but no practical use of it all he does is burn tomato atleast ur ones fly
i reckon get the 3d files , make the engine ,AND FLY
Issues to correct if you want to use this in a plane:
1. It weighs too much. Make it thinner, eliminate all of those bolts.
2. The shaft bearing is too large and bulky. Do you even need it? The rotor is made of Teflon which has low friction so maybe it can act directly as a bushing. Might help with sealing too.
3. Maybe go back to a 3 vane design now that you've changed the mechanism.
4. Experiment with different geometries for the exhaust port to exhaust faster and reduce back pressure. The vane is on an angle, so the exhaust port can match that angle across the whole vane length to the rotor along the swept area.
Bro, let us come with some genius solutions as well!😂
Somebody paid attention in their physics and engineering classes.
Check out the type of air seals used in jet engines. labyrinth seals. Also I forget what they are called. But there's little indented rings around mortar shells. Those help trap the gas without any friction with turbulence.
Of course both jets and mortars have a lot of gas so leaks are less of a worry than people think.
But there might be something worth stealing because they are both incredibly low friction.
He could also experiment with angling the vanes themselves, the same way the flaps were angled.
My first thought was to increase the number of flaps, but I see I'm way too late to post it.
Integza, about 23 years ago as my thesis project for Mechanical Engineering Technology, my friend and I designed a 4-bar mechanism that solved this problem.
We called it the QRP or Quick Return Piston, because it had a 270 degree downstroke and a 90 degree upstroke.
I still have the files and paper if you are interested.
Send it to Tom. Integza has his flappy engine now and can't go back.
Thats cheating. @MohamedTarikRochdi
Send it to both. Integza will make the engine
I probably don't have the technical expertise to produce anything from your thesis, but I'm very interested in reading it
Many ways to accomplish engines. I lean towards steam made by a rocket stove. Free fuel, simple parts.
3 design changes you might want to consider:
1. At 4:15 you throttled the engine via friction by reducing the nozzle size. Instead, consider adjusting the torque demand of your propeller (diameter, pitch) if you want to trade run time against power.
2. The rod idea at 11:23 is geometrically flawed: when it is aligned with both the centre of the rotor and the centre of the hub, it needs to be the diameter of the hub. However, at all other angles (especially perpendicular to this direction), it needs to be slightly shorter, as it no longer passes through the centre of the hub. Of course, this is no longer an issue with your flap design.
3. Perhaps you could add a flexible lip to the edges of your rotor that presses against the casing - through pretension and also through air pressure.
2. Doesn't make sense to me, the diameter of a circle is constant. Why should the rod change?
So here we go.
1. With only 2 vanes, the engine is pulsing. 3 or 4 would increase the surface area to catch the air.
2. The ball bearing is overkill, make the case tight around the shaft. Experiment with o rings or a ledge.
3. If you're regulating the pressure to 2 bar, then you can reduce the thickness and weight of the housing.
4. Instead of vanes, you could use disks. Alot like a tesla engine just small enough to save weight.
5. Rotating mass will be your friend for extended run times due to the light weight. Attaching the propeller with a larger single bolt will help the fluctuation in rotational speed.
6. Inceasing the size of the exhaust port would allow the air to easily escape, increasing the pressure difference on the inlet which would increasing torque.
All in all, a really interesting build and your build process is really relatable. Keep this series up until you battle Tom for air superiority!
The compressed air tools using this mechanism do usually have at least 6 vanes. More vanes will add friction but maybe still worth it?
If you add 4 flaps, you can also add 2 more inlets and exhausts (twice the power for twice the consumption)
More surface area more flaps makeit into a turbine
@@ns-li4pr Yeah, it's already half-way there with that tangential inlet port.
@@-danR The inlet Port should be putt more into an angel. Maybe 10° more degree towards the roation and three flaps. So the Air pressure is directed to the Flaps instead of "filling" the room.
0:30 shots fired 😆
Nice
6:32 with the subsequent "I'm screwed"
Oooff 😂
lol, Hi project air love your channel
U gotta hop on to this challenge i want to see my maker youtubers compete
Since the flappy engine has so much less friction, have you considered going back to a three vane or four vane, that way more of the pressure that’s coming in has a smaller expansion area before the next vane kicks in, I may not be explaining this correctly but a third or fourth vane should give it more torque and or speed, just note this is an idea before the end of the video, timestamp is 18:37…never mind I just realized the total length of the video😂
Also trash the bearings, instead make the rotor with the “shaft” built in and in the main block just have a blind hole and do the same on the front cap. That drops the leak area plus with it being made from PTFE, shouldn’t be much friction!!! {-o-} diagram for example!! Love your channel, and Tomatoes are totally gross!
@@studiowilds9879the mechanical strength and low friction in bearings is almost nessesary in this situation, any other mounting will be too much friction and too weak, but if he would add a simmering to make it airtight, it would probably work better, but more flaps could maybe be a trick as you explain above
I really like the flappy engine, because it was the 1st design that moved away from traditional pneumatic air motors used in air tools for the last century. Probably due to wear rates, but still, for the intended use it's a really well thought out work around towards efficiency, power and weight.
Also, introducing flexure to any mechanical design is the ultimate engineering flex - pun intended.
You should consider increasing the number of flaps from 2 to 3, and either enlarge or add another exhaust port at a 120° angle to prevent compression. The operating cycle of your engine should follow these stages: inflation (at constant pressure), expansion (until atmospheric pressure is reached), and exhaust (again at constant pressure).
In your current design, the expansion stage is inadequate, followed by a compression phase. This increases the overall pressure and wastes a significant amount of energy. The exhaust pressure should be equal to atmospheric pressure, so it might be worth adjusting the intake pressure accordingly. Finally, it’s advisable to resize the model to match the required output power.
Perhaps I wasn't clear enough. In the 3-flap model, the first two cycles perfectly align at 120°, and in order for the third cycle to also match, the engine would need to allow for an exhaust phase during the entire 120°. This could be achieved with a large exhaust port throughout the entire stroke, or at least two ports-one at the beginning and another at the end of those 120°.
If necessary, an additional flap could be added, as more flaps increase the expansion ratio.
In the 2-flap model, air is injected for 180°, and expansion occurs only for 90°, resulting in a much lower expansion. For 2 bars of pressure, a 3-flap configuration is optimal
I was about to write the same, then realized you explained it perfectly! Congrats
You are absolutely right about the harmful compression. The exhaust should be at 180 + 180/flaps degrees from the input. However, it seems kind of wasteful to let that portion of the rotation do nothing.
I think if he has already abandoned the use of mechanical sealing and switched to flaps, he can make the chamber oval-shaped. This way, the expansion phase can be longer than the narrowing phase, with more degrees of expansion. Theoretically, it does not make any difference, but it feels like a more gradual expansion would be better.
13:29 "Teflon, which is the thing in your non-stick pan" Proceeds to show us a cast iron pan.
Hey, it's "non-stick" 😉
Isn't teflon getting banned or something?
@@GewelReal yeah, no one uses teflon on non-stick pans for decades now
@@aflac82you can still buy Teflon pans here in the uk pretty abundantly unless it’s a name gimmick, why would Teflon be banned is it harmful?
@@aflac82 Teflon is a brand name, it's actually just PTFE. A compound that was used in this material was carcinogenic and got banned. Your non-stick pan still has a 'teflon' coating.
Stanton fans here
Stanton's pretty cool
so obscure!!
Don’t watch him that much but when I do he cookin
Could not believe he opened with Tom smack talk..
and D4A
Thanks!
Several improvements are possible:
1. Drop huge 2 psi valve and resort to using a 3D printed reed valve integrated directly in the motor. Why? Weight. You need the lightest design to successfully fly for a long flight.
2. Drop the metal bearing and simply make a PTFE centre shaft as part of your motor redesign. Both weight and less friction will result plus less leakage.
3. Your use of PTFE is great to reduce friction and also deal with engine heat, but you still need some lubricant to deal with the micro leakage. I suggest providing a amount of light synthetic oil via the central shaft where you made the bearing replacement. The centripetal force will dispurse the drop sealing not only the central shaft and lubricating it but will fly to the outside of your leafs and then seal there to provide seal plus lubrication to the leafs. You thus solve both leakage issues.
On a final note, the Tesla Turbine concept which you do not mention (since it applies to fluids not gases) could draw inspiration by potentially using the exhaust gas the the outer edge to a perpendicular disc adjacent to the motor with the disc dimpled with half clam shaped dimples to catch the air but using a logarithmic sizing of reduced clam size as you work to the centre that would be exhaust port. Despite air not acting with the viscosity of liquid as Tesla design, the clam dimples could assist to additional acceleration of the central shaft of the motor. Of course such fabrication was impossible in Tesla days but with a 3D SLA printer it is. The only downside is additional weight to add this and also size since the larger diameter disc provides greater efficiency in the Tesla design. Since you wish to fly, just stick with the original 3 points. FYI - a recall around 2008 when a company out of India called Tata was proposing using air as the new fuel. They did make a prototype car but I think it only went 30km/h and so for small city driving. No clue on their engine design but I always liked the idea of air as the fuel with the exhaust as the air that went in! The question of how best to compress it likely created the additional complexity that we never saw it materialize.
gasses ARE FLUIDS!
I like how you post all of this yet don't even know the basics of gasses being fluids.
1: that pressure reduction value weights 10x more than the motor itself. A reed valve sets a minimum pressure not a max. How would that work? TATA discovered that the air in India was too dirty and clogged the compressed air engine. !!
@@stephencaparelli7733 I felt so smart when he said that! Maybe I can be an aeronautical engineer after all! But in actuality, I work at IKEA, and yeah, no.
The Tesla Valve might be an option
The vanes (around 5:45) are being pressed back into the core of the rotor because there's a huge pressure differential between the outside of the rotor and the inside. It's air pressure that is forcing your vanes in. When the air pressure that leaks past the vane, into the center of the rotor, and out of the engine has dropped enough, centripetal force can overcome it and the vane closes again.
It would be interesting if there was a passage in the rotor where its entry went from the pressurized zone, through the rotor, and into the bottom of the vanes' "cylinders" so that the pressure is equalized.
Alternatively the centripetal force could still overpower the pressure differential if the diameter was made larger or the vanes heavier (v^2/r).
Mechanical engineer here. I'd be happy to provide sketches of either!
@@fernandosaenz4196 springs are always the answer to things like this
Ditch the bearing, use straight teflon on teflon. Machine the rear housing with the shaft your rotor sits on (rotor axle and rear housing is one piece) axial drill from the back into the shaft portion, not all the way through, and then drill a radial hole on the shaft. This will be your air inlet. Now on the rotor, machine it with the propeller shaft (as one piece) then drill 2 axial holes (on the rotor) to the center in a way that times the air inlet at the correct spot in the rotation of the rotor. (rotor shaft hole placement will be tougher to time) I would suggest a taper fitments at the base of the rotor shaft, and base of the propeller shaft, this will aide with thrust sealing caused by air pressure and the thrust created by the propeller. The blow by air (should be minimal) will help reduce friction and cool the teflon on teflon bearing. Obviously, you will need matching tapers on the rotor shaft to rotor and the rotor to outside cover. This design, in theory, will reduce friction and eliminate gaps (only 3 pieces now), reducing your escape losses. The hole on hole setup (when the air inlet hole on the rotors shaft lines up with the hole in the rotor) will act as the regulator, much like that checkball on the other guys motor.
Even just ditching the bearings and switching to a teflon bearing surface would be a big win
A Teflon bushing?
@DavidMulligan yes, but a bit more complicated. Using the air pressure to act as a cushion between the teflon pieces. Also lessens the amount of pieces, making less areas for loss.
Good point but probably you will need somewhat more pressure to make it kork properly, spetially having into acount the angular inertia of the blade
@@CrespoTorke8 That's why I mentioned tapers
The connected vains idea was a display of ingenuity.
wait for the flappy things
vanes
That confused me... I'm not understanding how they were both always in contact with the outer cylinder, when they were spinning in an offset radius; was there a spring in that shaft?
@@userzero9259 it doesn't matter that it was offset, all the matters was that they stay the same distance. if you're good at visualizing, imagine focusing on just the rod. it doesn't matter what else is rotating around it, it's just getting pushed back and forth from the pivot's POV
I LOVE the childlike naiveness of youtube comment section. It's not like pneumatic engines have been practically solved for years if not decades and literally anything seen in this video isn't new nor unkown to the content creator beforehand.
He's not even that good at pretending coming up with new solutions or being surprised at things like..... not using any lubricant, LMAO.
Use less diameter bearings to reduce the area of leakage in them. Also, it's better to have more volume of the engine cuz it improves the ratio volume/leakage.
Sealed bearings should also help
I believe if you have more volume in the engine the running time will lower because air in the bottle is still the same so % of air that is wasted is higher
Also smaller bearing makes it lighter. Higher chance that it flies.
Or 0 ball bearings, since it only runs for a couple minutes he could just use teflon sleeve bearings/bushings with some light oil or grease. Also if he was to change the drive shaft to steel he could use a much smaller diameter which would result in lower leakage around the output.
@@balrog240Sealed bearings would have much more resistance too
There is nothing sacred to him.... everything is a rocket for him
Great work. I would love to see one of these as a range-extender.
make the engine housing from another material that is harder and lubricate it with graphite
powdery graphites are gonna stick in bearing lubricant and can slower them down
The advantage of oil is that it also works as a sealant.
@ojaswiagarwal-x1y 2rs bearings after time will not slower an engine
@@FedericoLucchi who said u cant have graphite and oil? i remember some old car oil had graphite in it
@dominikvarholik7519 zink.
A way to eliminate some of the leakage as seen at 12:40 can be using sealed/shielded ball bearings or even better, fluid shield bearings! not only it'll eliminate the bearing leaks, it'll help the engine run smoother since the bearings are constantly lubricated.
I was thinking all the time the same!
From what I'm seeing, you're putting more air through the stuff and never letting it out, that's why you get leaks.
There are 2 chambers separated by the vanes.
The first one gets the air intake and it's volume grows, that's fine.
The second one has a somewhat constant air quantity, but it's volume shrinks, it builds up pressure, resists the movement and ultimately generates the leaks. Add an outlet hole in this chamber.
If i'm right you might get a better seal, and less resistance from the outlet chamber.
At 10:33 you can see the hole in the model. I highly doubt Integza was unaware of this.
My background is industrial maintenance. My recommendations are simple. 1: Enlarge the end of the housing to accommodate a lip seal on the shaft. 2: Put the on/off valve between the pressure regulator and the motor. Air flow does act funny sometimes. 3: Enlarge the housing to a pill shape and supply air to the second chamber. You may have to reduce the size of the restricted orifice going into the motor.
Just some ideas.
Oooh, so pressure regulator fills the reservoir, which feeds the engine
As an engineer I've seen something similar in a marine application here's what I suggest. Use a 4° reverse vein use your pushrod design. Use graphite powder dry for a lubricant and gap filler. Your central peace should be two parts to clamshell against the veins and the pushrod unless you can get tight fitting as single piece. You may even be able to go to a three vein 2° reverse angle using a cam style to move the pins in a direction to keep the veins close to the outer shell. And you could then use a nitrite seal or similar automotive style seal on the output shafts of your rotary vein. That would minimize your parts your escape portions if you do the tight tolerance thing again with the seal it would keep everything much tighter with less friction minimizing your parts and less air gap
This guy is probably gonna win :/
The 2-part clamshell to get a tight fit around the sliding vanes is a good idea in theory. But that gap is already eliminated by being the solid attachment point of the flaps.
"veins?" ----> *vanes,* dude lol
NOBODY CARES!
This is awesome. I love this little flappy engine; I think you have landed on what could be the new gold standard design.
Please check the sealing on the piston's axial direction. If you machine annular flap seals into both piston faces, remember that the propeller is pulling the piston towards the front, so the seals on the back face of the piston will have more clearance.
For even better sealing and less friction, you could make the entire expansion chamber PTFE, using the resin housing for structural support. Or just machine a grove in the housings for PTFE o-rings.
Finally, your bearing isn't the best one for an airplane. You need a thrust bearing in the front of the engine and a sealed bearing on the rear. The front bearing and engine housing is taking all the load of pulling the airplane forward.
Quick, simple, and requiring no major container changes: Increase the number of flaps. I KNOW you reduced the VANES to 2 to reduce leakage; however, flaps are different because the pressure increases the seal. Thus, more vanes means more torque AND without sacrificng sealing. NOTE: I am NOT suggesting going from 2 to 3; rather I AM suggesting seeking a sweet spot which might be 3,4,5, etc. to find the optimum between the net increase in friction with the net decrease in leakage. You MAY need to simultaneously seek a sweet spot with regard to pressure as well. Hope this helps. BTW, I love your presentation style.
i think it very much depends on how much friction each vane/flap causes, if there are two pressurised cavities (implying 3 vanes/flaps under some pressure) then the mid vane has pressure on both sides, albeit that the pressure in the cavity nearer the inlet ought to be greater than the cavity about to exhaust.
It's not that simple. If you have too many the airflow into the chamber gets cut off too soon. Most energy is probably extracted between 30 and 60 degrees after the inlet. With two flaps the movement after 60 is not helping much. With four or more you are not maintaining full supply pressure throughout the productive part of the cycle. It could be calculated more rigorously but my gut feeling is that 3 may be the optimum. You are right, his reason for moving to 2 has gone, he need more flaps.
@@nomdefamille4807 Thank you for your well considered response. In my mind I pictured sort of a water wheel -- but you may well be correct. I am not much of an engineer; I have always taken the million monkeys approach -- admittedly, more tortoise than hare; but it usually works in the end.😀
@@nomdefamille4807 Thank you for your insight. You are obviously a much better engineer than old kitchen chemist me. I had visions of a sort of water wheel efffect; but, that just might be the amateur in me. I still think something along those lines might be worth a shot. Who knows; even if it fails, it just might provide some iterative inspiration. 😀
@@tuberroot1112 FYI Commercial vane motors can have up to 10 vanes. It appears to be a judgement about lower friction vs lower internal leakage and RPM. As long as the vane still has space to expand outwards then the air can continue to expand. Given the inner rotor is offset from the outer, the rotor can rotate 180º and continue to expand.
I just randomly happened to have this video pop up. I know nothing about air engines. But, this comment section, which I see as a super nerdathon...
Is probably one of the coolest things ever, seeing everyone providing so much help towards creating perfection.
I wish I could be like all of you.
Man, this air rotary engine idea is crazy! Imagine using a nautilus spiral for the chambers resulting in smooth airflow, less turbulence, and max efficiency. Pair that with interlocking rotors, kinda like layers in a satellite design, and you’ve got continuous compression with almost no stress on individual parts. Oh, and dynamic balancing? Add some flywheels or counterweights to keep it running steady even at high RPMs. You could even go modular by stacking rotary layers like pancakes for more power and redundancy. And instead of just air, tweak the design for steam or gas mixtures too. Ducted pathways with adjustable vanes? Boom, variable compression ratios on the fly. Seal everything tight with optimized D:d ratios for minimal air leakage. This thing could integrate planetary gears straight to a generator or drivetrain, no problem. Test it out in CAD first to get those nautilus chambers airflow-optimized. Legit hybrid engine potential here!
Id love to test things like this myself… working towards that 3d printer lol
I think you should add a gear train to the engine. Also a teardrop exhaust port would probably help exhaust pressure to increase overall preference. You could use a seal or an o-ring around the shaft to prevent loss of air pressure.
Nice use of a compliant mechanism,
It might be nice in a pump too
@@orestdubay6508 Yep my 50 year old marine engine used a vane cooling-water pump with "compliant" rubber impeller, It's a far older design than you think. Making it low friction is the challenge here though.
Given the friction, what about making the flaps replaceable tabs that lock in with a key fit, but doesn’t add extra leaks? After enough run time the flaps would wear down like apex seals do.
Given the leakage occurs through the bearing, the bearing itself could be extracted from the main piece. It would be kept aligned to the rotation center axis, but only sustaining a center rod with minimal radius to be sealed against the pressure chamber.
You are correct, once he switched to teflon, bearing is just extra weight.
5:30
Van is sucked back to center because the chambers are expanding, but the inlet is blocked by the next van.
The air tends to move from high pressure area(the chanmber just finished filling air) to low pressure area(the expanding chamber on the right).
This design is not air tight at all so there will be tremendous air flow between the chambers.
The van is moving out due to centrifugal forces, which also created a low pressure area near the center of bearing.
All above is just my personal analysis, hope this can explain something to you.
Simply fantastic work!
The pressure regulator acts like a restriction in the feeding line. The pressure drop is wasted energy (deltaP X Flow). You can compensate the pressure variation (and, thus, torque) changing the excentricity of the engine
Higher the excentricity, higher the torque for the same air pressure.
Note that, initially, when you have higher pressure,you will need a smaller excentricity to generate the needed torque. Lower excentricity leads to lower flow, thus reducing compressed air consumption.
When the air pressure is low, at the end, the excentricity is increased, sustaining the needed torque for longer.
This can be achieved with a movable engine housing, actuated by the inlet pressure
Look for "variable displacement vane pump"
Greetings from Brazil
I'm not convinced you're from Brazil, because you haven't invited him to come to your country yet, hahaha.
Yeah, I noticed the waste of energy in the pressure regulator as well. You reduce the pressure, but the amount of air molecules that are in the bottles and can go into the engine stays the same.
But wouldn't an engine with zero eccentricity waste air molecules instead? Yes, you get less force, but the air coming into the chamber is still 2 bars (or actually even more), and the "input cutoff size" of the chamber (the size at the point when the input port gets cut off) is basically identical to the "input cutoff size" at maximum eccentricity. And any time the chamber reaches the exit port, the pressure in it is still dumped from X bars above ambient to ambient pressure, even with zero eccentricity. I have a feeling that variable *eccentricity* only works for pumps.
For engines, you probably want to keep *maximum eccentricity at all times,* but "vary the position of the input port". With high pressure, you want to input port right next to the "apex" (where the rotor touches the housing), since the chamber is smallest there. But for lower pressures you'll want the input port moved to (or a secondary input port opened at) 90° from that position, where the volume change of the chamber is highest.
And obviously, varying the position of the input port with respect to the point where the rotor touches the housing can also be achieved by shifting the rotor axis, so that the point where it touches the housing moves with respect to the (fixed) input port.
I LOVE LOVE LOVE that you took on this challenge.
The pneumatic engine removes combustion dangers, allowing everyone to try new ideas on one of the most useful components of the modern world.
Converting stored energy into mechanical rotational energy.
Years could be spent tinkering with pneumatic engine designs. Its incredible the varied possibilities that exist, things that have never been thought up just waiting to be discovered.
My favorite video EVER that you've created.
Except needs more exploding "Tom"atoes.
Or you could just look at a Wankel
Can u try to make a tesla turbine with this method?Nice video i love it!!!
I think the torque would be too low especially at the start. 😢
The whole point of a tesla turbine is to blow air directly on a set of discs, so unless you mean "scrap everything you were doing to make a Tesla Turbine instead", the mechanism he's using inside is taking up the exact spot he needs to make a turbine with.
esses motores funcionam melhor com fluídos que possuem viscosidade maior e é bom usa-los a uma pressão alta e constante
@User__Not__Found
Using this method, could you breed 2 giraffes?
Brilliant video! My 2c below in 10 points. Difficult to put into text but I'd love to be able to discuss further. So much to elaborate on.
1) Balancing:
Kind of speaks for itself, but balancing anything that has rotational forces is a great start. I wont waste text on this point.
2) Number of vanes:
I would go back to 3 vanes min. Doing so would reduce weight and also allowany of the following ideas to be beneficial.
3) Vane and running surface shape:
Make the vanes rounded at their ends where they meet the bearing surfaces and as such the outer walls/extreme running surfaces should also be curved to match. Hydro dynamics tell us that square edges only create drag.
4) Bearings:
Perhaps try a "mag lev bearing" like the ones used in "Sunon" computer fans to reduce friction.
5) Sealing:
A micro fillament material or even something such as lambs wool which is self lubricating, heat resistant and waterproof (so it won't wick moisture from the compressed air which would cause excessive friction) for the vanes along the outer edges which contact the outer running surface and side walls.
6) Weight:
Will likely increase with above proposed bearing however rotational mass lends inertia which will also increase lending to use of different propellers.
7) Propellers:
Propellers are potentially the most interesting part of this application and depending on the size, shape and purpose of the machine you wish to propel, will have possibly the greatest significance. Going into this in one (already too long) comment isn't possible.
8) Power run/pressure side:
Shorten the length of the power run but add vanes and make the chamber a "snail shell" design so that the maximum pressure of the chamber becomes more constant. Ie. Larger at the initial point of pressure, reducing in size towards the end of the power "stroke" so the increase in volume of the chamber doesn't expand so quickly and drop off before the next vane picks up the new power run.
9) Porting:
Soooo much to do here! Rather than trying to eliminate pressure leakage entirely why not try manage/redirect it?
First play with port angles and shapes of both intake and exhaust.
You could create a gradual exhaust port using a contracting slot in the outer wall/running surface being max open at the start of the exhaust run coinciding with the start of the following vanes power run. This port would reduce to zero at the end of the exhaust run just BEFORE the leading vane begins it's power stroke/run. By doing it just before, I'm hoping you might be able to create a slight negative pressure to help the vanes slip easier using air as the lubricant in the micro fillament (or lambs wool).
But...! EVEN BETTER than both of these would be "NO MOVING PARTS PORT TIMING" by using a tube entering the outer wall at an angle so as to create an oval shape (the fixed shape of which could be altered by the angle at which it enters the inside wall) would essentially gradually open and close an exhaust port as the vane passes over it with the angle at which the tube enters changing the shape of the port. The "timing" part comes in as you can then route the exhaust back to the pressure/power side wherever it is now greater than the initial pressure of the vane on the current power run accepting losses on the system due to sealing issues. Routing this exhaust via a seperate run gives the ability to recycle much of the pressure and have it enter at a given point to add pressure to the power chamber and keep the pressure more constant as it expands with the passing of the vane whilst it moves along its power run.
Playing with the shape of this exhaust chamber and timing its relief (via expansion rate) and then adequate compression rate for the next stroke via compression would be very interesting indeed and much like using a 2stroke expansion chamber which on a highly technical level, I'm sure even the acoustics would have an effect (and if by some miraculous means your project somehow gets to this stage... Best to send it off to Yamaha me thinks... Those who know, truly know).
If you had the tech available, this exhaust route could be made of a UHWMPE microfibre to keep weight way down but when pressurised would maintain a constant shape. The density of the weave on such a fabric could even allow the ability to bleed off unwanted pressure for a given application.
Alternatively, porting could even be used to run exhaust or initial pressure through a central turbine fan shape if the central bearing allows through-passage.
10) Friction:
Eliminating friction as soon as possible after the exhaust run may also be possible by removing as much of the walls and/or outer running surface after the exhaust run also helping weight reduction of the unit without affecting the rotational mass needed for enertia.
I'd love to try designing something like this and see the effect of each stage.
A 3D printer would definitely help... Just saying 😁
THE LEGEND HAS UPLOADED ONCE AGAIN!
Yeah, I was starting to get worried about him.
Hello, in order to reduce leaks between the transparent plate and the rotor, you could install a series of 2 or 3 baffles, they are used in applications with very high rotation speed and high pressure. I remember this passage from my engineering classes. With the tolerances of your printer this might be possible. (sorry my english is bad it's not my native language)
Edit : There is no friction with this solution, because the two parts do not touch.
I was thinking some matched up oil grooves for the same leakage points. since it's a short duration doesn't matter much but needs sealed.
and a frigging o ring around the main body and clear plate. once the spinny bits are better sealed, that body is going to be the next spot.
I also thought he should try to stop that "3D" leakage. Perhaps the transparent plate (and rotor) shouldn't be flat.
No your english is not bad
@@Noksus thanks 😅
Like the set of grooves on a piston?
The pain of air engines...it's so addicting hah! Best way to reduce friction of the rotor further is to reduce contact area against the housing faces. So just have a small lip around the whole edge (plus the whole flap of course). Less area means less friction so you can have a tighter fit for less air loss and same friction. Or same air leakage with less friction. Really clever design, how long do those flaps last before fatigue failure?
They haven’t failed yet, Teflon is actually very resistant to fatigue stress
Contact area isnt really important for friction. You have to reduce the normal force and the coefficent of friction.
With the rotor fixed on the ball bearing and effectivly flying in the housing,giving the rotor - housing clearance a thight fit, you could increase the almost contact area there and smear it with thick grease to seal it.
Doesn't a smaller contact area mean there will be a greater chance of air leakage?
@@AA-rc6ob Should be less. Any point of contact is an opportunity for leakage. The force at any point of contact is directly proportional to the pressure - it doesn't matter how large of an area there is. However, the amount that manages to sneak through per area also depends on the pressure, so if there's more area, there's more total flow through that area. This is why his smaller nozzle provides longer runtime but less torque - it's the same force coming out per area of the nozzle but there's less area so less total flow.
It took me nearly 30 years to finally enjoy the taste/texture/nutritional content of tomato. I first started enjoying them when I grew a cherry/grape tomato plant on the patio called "Sun gold" Their taste is very good, especially right off the plant warmed by the sun.
Can't wait for Tom to make a new one, and this to turn into some mad competition
More, longer, thinner flaps.
On the exhaust side, you need to make it easier for the air to escape.
Fill it with graphit powder as lubricant one time.
Yep, a dry lubricant would be beneficial, though I would go with molybdenum disulphide.
Yeah he went dual veins because of sealing and springs and kept it as he went to flaps but with the flap designs there is no reason to keep only two veins. Not sure if more veins will help getting better results but it should be tested for sure.
@@gg4760-k5n Three vanes will probably help, because as-is air inflow can leak over the back of the rotor to reach the exhaust and lose pressure. Three sections will allow a filling section, a power section, and an exhausting section.
would graphite powder help when he's made the entire rotating assembly in PTFE/teflon though?
I fully agree with the bigger exhaust though
more longer, thinner flaps makes for turbine, but that'd be heavier and brittle - engine that works till first touchdown? 2. Do we really need to sal friction of teflon against teflon? Doubt.
Hi Integza, Phi here!
I have a bit of experience with vane motors and vacuums pumps. It looks to me like you can solve a bit of your tolerance problems by making your rotor larger, and the vanes shorter, in your flappy motor design. It will give them less opportunity to flex under the air pressure, and allow for you to run it faster or at least more efficiently. For the vane design on the other, narrower vanes are better, but the cavities should be sized such that there are extremely tight tolerances, and when the vane is fully extended there should be about 2/3 of the vane left in the gland, otherwise friction will try to drag it out of its space, causing more friction, and eventually self destruction.
Gaskets and rotary shaft seals are grand!!!
Three vanes are better than two in all regards.
Cheers!!!
Great video. Using a pressure regulator adds weight. Try using an adjustable throttle valve instead of fixed diameter aperture. It also makes experimenting and testing a lot easier. To save on weight, instead of trying to fit Your engine to the plane, build the engine so it attaches directly to 2L bottle. Let the bottle become the fuselage and just add wings and stabilizers to it.
The Flappy Engine has to be one of the most technical names ive ever heard.
Another name for it could be a Floppy Drive 😅
@@Simpayne68Wwell played 👏🏼
If you also put the flappy flap on the side the engine would have an even better seal.
Also, test again with 3 or more flapy's at a lower pressure. Maybe you can increase the runtime even longer.
As an engineering educator, this is shuch a great video: how to design in Engineering. Thanks.
Greetings inventor, I am Lucas Freitas, I am an engineering student from Brazil, recommendation for the upgrade:
1 Use sealing rings on the fitting parts
2 Add shielded bearings
3 Use car cylinder head sealing glue around the mechanism;
All this will help keep the air where it should be
Otherwise the engine is very good.
I hope it helps you based on previous experiences
you should make the exhaust port bigger so the engine has less resistance while pushing the exhaust gasses out
3:50 your bearing don't rotate
Think the tiny balls are doing the work
👀
Doesn’t have to, the bearing isn’t connected to the outer wall
My favourite video of yours. It's just one good idea after the other.
Good luck kicking Tom Stanton's 🍅
Quickest/easiest fixes:
1. 3D-printed flap mechanism + teflon housing. CNC cutouts around flaps increase the volume of air wasted. Maximize pressure differential vs volume per compartment.
2. Print versions with different amounts of flaps. Finding the correct amount in theory will take forever. Just print versions with 2 up to 5(?) flaps and see what's most efficient. No math needed.
3. Use a liquid, plastic-compliant lubricant. It's basically a free sealing agent.
4. Ball bearing in the center really makes air leakage too easy. Teflon center shaft and a lubed bushing would have just as little friction and be much easier to seal.
5. The front and back wall need to keep the air in the flap compartments. Look up a "labyrinth seal". Perfect for rotating designs, easy to implement, basically zero friction. Add the lubricant, boom, got a great seal.
6. Where is your outlet? It wasn't entirely clear in the video. Just make sure the air escapes quickly after the halfway point, otherwise the engine is working against itself.
7. Housing with a nautilus shell shape, but with a very smooth transition, so it doesn't wreck the flaps or cause them to catch. Then you can use almost the full rotation for expansion. Adjust outlet position accordingly.
8. Make sure the back wall is stiff enough to make the deformation due to axial force from the prop negligible. Otherwise sealing the flaps will be even harder.
Those are all the easy ones I can think of.
Edit because I was being dumb.
Flappy engine was a massive improvement. I am a little surprised that you did not make the flaps in a way to push against all walls. not just one.
Super fun video! Thanks for creating an amazing content.
Please make a version 2 of your turbo jet engine that will run for longer , it was one of ur best videos, I too felt the joy when it started working , plsss.
that was one hell of a thing
Yaa I felt the excitement too😉
UP
I know I'm too old for a Make-A-Wish, but I hope fate lets us hangout within the next 18-24 months.
Making a project with you is definitely on my bucket list. You seem like a genuine and funny person. Both of which I could really use right now.
Armchair Design Ideas:
1. Increase the number of vanes to at least 3 to ensure at least one is always producing torque.
2. Progressively port the exhaust (teardrop shaped passage in the back housing) so excess backpressure can begin to vent as soon as that flap's specific trapped volume begins to decrease.
3. Buy a one-side sealed bearing so air can't leak through the ball race.
4. Clamp and glue the case instead of screwing to reduce mass (design in alignment tabs).
5. Build a small sliding-spool pressure regulator into the inlet because the one used for testing is entirely too heavy to fly.
6. Make the rotor wider (deeper?) and the vanes shorter so the conformal hinge doesn't have to flex as much, and your average moment arm will be longer.
7. And the crazy one: Commercial pneumatic vane motors sometimes use inlet air pressure to load the vanes against the walls instead of springs. The air is ported through the housing, into the rotor, and delivered into the rear of the vane cavity. Big advantage because the friction is directly related to supply pressure, meaning at light loads, you will have less parasitic loss. This might not work with flaps normally, but... since you have a resin printer, what if you modeled a Bourdon tube (like a pressure gauge or a party blower) into the vane to act as the spring?
The pressure on the tip of the vane is why it was popping inwards
What especially kept me on this video was the detailed explanation of the occuring flaws of your engine. The light nagging to tom, the 'ping' of cutting the spring at 6:05, the 'farting' engine at 11:05 are the small things, that are the cherry on top to me.
@integza 11:23 axis isn't in the center, so when it is perpendicular to the vector of change (I hope you understand) ends of the rod touches 2 sides of the circle, but when it is parallel to the vector the distance between end 1 and end 2 is a diameter, what basically means the rod is too short.
summarizing, springs were better
Yea that brought my attention too. It either make terrible friction or will be totally leaky.
6:40 Oh... it's the same problem that every real world wankel engine has: leak from the side of the rotor.
Use a tight fitting teflon/nylon bushing instead of a ball-bearing. You get a better seal and lower weight. Downside is it wears out faster, higher friction loss until it wears-in. Pack teflon tape around the crankcase cover for better sealing.
Use powdered graphite lubricant instead of a liquid. Less fluid drag and it eventually builds up to form a seal.
You can probably swap out the metal bolts for polymer ones to get the weight down. Every gram counts.
To improve this wonderful tiny thing:
1. Center the air intake as much as possible for the airflow to hit the flaps (it's not about max torque, but about the air efficiently pushing them)
2. Make the flaps into a pelton turbine shape: if it's efficient for water, it's probably great for air too!
3. Get a bearing with a rubber side: a lot of pain was leaking through the bearing!
4. as @naasking was saying, experiment with 3-flap design and try to reduce back pressure
5. find the optimal width: with eiter software or a couple of prototypes, surely there is an optimal width that maximizes torque without killing rpm.
I hope this helps! Much love from Italy!
the traditional pelton wheel gets its advantage over the venerable water wheel by providing a course for the fluid to reverse direction in to an "unconfined space", so for that aspect the air needs to leak out. here i think he needs the torque of the "rotary piston". if he is currently running for 3 minutes against a need for 2 then he could open up the inlet nozzle slightly and increase the depth of the rotor/ motor. he really should try and dump the regulator, the assembly would better use the stored energy if it could withstand peak soda bottle pressure. and in terms of flight performance anything to reduce weight, as all others have pointed out.
@@nomdefamille4807 great point
The engine doesn't work because of airflow, it's the pressure differential of the air expanding inside the chamber that causes it to rotate.
@@NeilStansbury And what is an airflow/wind if not a pressure difference, you 'genius'?
@@dziubo1 I suggest you go and have a conversation with Mr Bernoulli and ask him to explain his gas principle to you, then you might be able to answer your own question.
add a ball valve before injection, reduce chamber size, make a spiral to open and close the ball valve only when you need it for the amount of air needed to achieve the rotation you need.
It would be so awesome to see a collab!
First, one video that pits you both against each other facing an engineering problem,
then another video in which, together, you both integrate the best of each design to produce the best possible solution!
INNOVATION MUST COME NOT ONLY FROM COMPETITION, BUT ALSO FROM TEAMWORK!
Suggestions:
Try using a low viscosity vacuum oil to help seal leaks.
Cut a tiny flap at the edges of your rotor to help seal at the acrylic front and rear, like you did when replacing the vanes.
Use a very small food grade sealed ceramic bearing to eliminate leaks through said bearing.
Try cutting a deep groove/slope just before the flaps, towards the center of your rotor so you can make the flaps much longer and improve your F=P*A ratio.
1:23 fricking finally
18:32 I would think that combining your flap design with your vane design would be best. Like a vane that has a flap sticking out of it, like a y ... you also might consider an o-ring seal around the core of the rotor, against the walls of the chamber. to prevent air from leaking that direction.
To improve: make side-flappies on the flappies and the rotor body to eliminate leakage against the flat surface of the housing body. Play around with angle and position of the entrance. I have a gut feeling that says you will get better yield at 5° further and slightly steeper stream angle (which now is perpendicular). And perhaps bring back the 3rd flap. Also, adding a second exhaust hole where the inlet no longer feeds the cavity, will reduce friction in the second half of the rotation...
Lets call them micro flaps (on the sides of the flaps). Why not have a slit for the exhaust (about 1/3 or 1/4 the width of the flap) extending around the back half of the motor for about 170 degrees (just under 1/2). No idea if these will help but they are ideas to try.
So many good comments already...
I think you could increase efficiency by limiting how much the lips need to deflect (loose energy in deformation) but that is probably minimal. The exact angle for the intake and outage round your motor should be planned properly also to make sure that air is expelled at wanted pressure outside the chamber (basically 1bar)
Just make sure that when you're making the plane it's built more like a glider, so it's easier for you to keep it in the air even when the air pressure drops
15:05 HEY NO SWEARING
When I buy any 'cheap' air tool, I run it for a baseline, then tear it down and check everything using a granite surface plate and Prussian Blue. Once all the parts fit, lapped, sharp edges chamfered, orientations to ports corrected, that cheap $20 tool will almost always perform like an expensive brand name tool. Love your flappy design and your follower vane, I can see real world applications in my future.
shh that's the secret dont tell anyone
I enjoy how you trouble shoot through the issues, great to watch.
To try fine tune your flappy engine, now that you have resolved your leaking issues, maybe reverting back to more flaps now. I would assume it would work on the same concept as a two stroke engine and a four stroke engine… produce more torque at lower rpm, generally have better durability than high-revving two-stroke engines and also provide improved fuel efficiency. 🤷🏼♂️ I’m no engineer but love trying to figure out how to make things better.
Lubricate the whole inside with plumbers grease. It's thick so will help seal any tiny gaps but keep friction low. Worth a try.
Grease will slow the whole movement. Low friction and light parts use very runny oils for lubrication. (if you drop a small screw into a blow of grease, it wont roll out of it anymore)
The slower or heavier the movement, the thicker the lubrication gets.
Using teflon as material eliminates the need of lubrication.
Looking for this advice. A very thick oil can provide some sealing
@@juvenildr So does superglue. You still wouldn't use it on small moving parts ;)
Grease (plumbers being one of hundreds of types and proporties) will act as a small liquid gasket sealing any tiny air gaps. Teflon may be friction free, but you still can't machine Teflon to run with no air gaps and expect it to be free moving. There are some greases that thin out when heat builds up, and although this air rotary design is only air, the compression then expansion of the air, through the motor, will generate a small amount of heat. Plumbers grease will thin out slightly with the heat yet still provide a reasonable seal. If not plumbers grease, there will be a grease that will be perfect, but it needs researching properly.
The blue liquid he pumped in showing the leaks is a good example. Imagine the liquid he pumped in smearing all around the front window of the motor. There's your liquid gasket. Or one huge liquid rubber washer so to speak.
16:43 adding a pressure regulator will make the engine run for longer but you are also adding more weight again. You're going to come to a point where you got your engine design perfect and then realize it still won't fly because it weighs too much
He could probably just make like a 3D plastic printed nozzle valve system that would cut the weight
3D print a seal on the ball bearing, similar to a sealed bearing (or try a sealed bearing?). I suspect that reducing this source of air leakage will help. Also try adding oil into the chamber before you screw on the cover, instead of just pouring oil through the bearing. This oil may help take up some of the tolerances.
Apply 2bar pressure INTO the bearing, through the ball cage and chanel the air to chamber/s. Used air exhaust opposite side to atmosphere.
Ideas to Improve Your Design:
1. For sealing: I would modify the rotor design so that its sides are flat with grooves for rings. These grooves should be slightly off-center with respect to the axis on each side. The blades should be positioned in the center between the flat faces of the rotor or between both groups of rings. Part of the blades should be cylindrical, located approximately near the rotor's center, where I would place rings to prevent leaks from the blades. I would also add seals to the rotor shaft where the bearings are located.
2. To enhance performance: I would utilize the Venturi effect to create suction at the exhaust by using pressurized air at the intake. This would improve both performance and efficiency.
I also have ideas for the lubrication system. 👍💡
If you notice, the two engine models are inversions of common compressor types. The first one resembles the piston-type compressor, and the current one is rotational. However, there is still another type to consider: the rotary screw compressor. Perhaps, by applying compressed air to a lightweight resin-printed, adjusted version of this type of compressor, rotational motion could be achieved more effectively, as the rotary screw design is the most efficient of the three. Only check the friction and leaks of air
Hey there! I just watched your latest video on the compressed air engine, and I have a few thoughts and suggestions. First off, you removed one vane, leaving only two, and replaced them with those floppy things. Remember, as you mentioned before, more vanes generally mean higher RPM and power. So, have you considered adding more floppy things instead? Speaking of improvements, why not try lubricating the engine with graphite? It worked well for the rotary engine in your previous video, so it might be worth a shot here too. During the leakage test, I couldn't help but notice some noticeable leakage around the bearings. That might be something to look into. I'm a bit curious about your end goal here. If you're aiming for maximum flight time, the two-bar setup might be sufficient. However, if I were in your shoes, I'd consider increasing the pressure up to 2.5 bar for better power output. Lastly, when you eventually get this contraption airborne, I wonder if the pressure regulator might be too heavy for successful lift-off. Have you considered its weight impact?
Keep up the fascinating work! I'm looking forward to seeing how this project develops.👍
I totally agree 👍
At least rewrite in your own words what the AI outputs my man
Yeah I know, but I'm not English. I'm just shit at writing in English. It's also not necessary I mean no one will ever read this besides you. So yeah the translator does the thing for me.
The flaps could be made more robust as a pivoting hinge (it would probably introduce another leakage point, but might be worth a try). The hinge would just be a cylinder embedded in the circle. From the top, the hinge would look like a comma, with the circle part of the comma inserted into a corresponding round cavity in the rotating circle.
That air flap at around the 14 minute mark was freakin genius!
I was thinking about wankel engines and how the apex seals work, trying to figure out how to redirect that rouge air and you did that, fantastic!
You should check out the Di Pietro Rotary Air Engine. It operates on a principle similar to the pneumatic vane motor, with greater efficiency but can be harder to manufacture,
It's an inverted vain engine like liquid piston design for Wankel, interesting
4:39 spun is correct 😊
Hey integza, try making a dyson-style fan only using ion thrust
"Hey Integza! I absolutely love the concept of your air engine, and I have a suggestion to improve its efficiency. What if we try using curved blades instead of straight ones? Curved blades, similar to those used in wind turbines, can capture more air and reduce drag, potentially improving the engine's performance. Additionally, if you used carbon fiber for the blades and housing, it would be lightweight and strong, which could reduce friction and make the system more responsive. Lastly, how about adding a pressure regulator to control the air intake more precisely? This could help manage energy better and improve the consistency of the engine's output!"
Maybe you could try graphite powder to coat the internals, which would also reduce the friction, It would be like having oil but completely dry.
I thought graphite was slightly abrasive?
4:30 your ball bearing is 100% not spinning.
Add a casing around the motor and connect the intake to the space between the motor and the casing. This space will then be pressurized, preventing air from leaking out of the motor. It is particularly important to ensure that the shaft penetration is properly sealed.
You'd still have to seal around the bearing and the rotor so the intake chamber doesn't leak into the exhausting chamber.
HEAVY!!!
Hi! Cool stuff, i admire Your process!
I have one comment - it's not so intuitive, if You're used to electrical motors, but air engine like this consumes more air when running without load! So when You adjust the nozzle to make the engine run for 1 Minute as initial design, propeller should be installed.
But it doesn't change that Your leakage optimization is very cool and would have been necessary anyway to get this overall efficiency.
Maybe in a future project You can build fitting lightweight tiny proportional valve to control the rpm of Your plane, instead of this fixed nozzle ❤😅 This would also increase the flight time when You lower the power and glide 😊
Anything You'll do will be fun to watch anyways 😅
18:45 Hero's engine is truly awesome, so is yours!
oooo an engine that works via compliant mechanisms, that's fun!
Biggest issue I see is that you probably have quite a bit of wear on this engine, even with such a low coefficient of friction, right? As long as it runs, it runs great, but eventually the pieces will wear down so much, you get too much leakage again, I think.
With the flexure version you *could* try going for a three-finned variant again. Might be even better? Though two-finned seems to work rather well
To increase durability, you can make the flaps longer.
Right now it looks like they are just about the ideal length for maximum leverage without leaks, but when they wear down it will very quickly start leaking since the flaps won't reach the edge anymore.
So for a more long term engine, I would add maybe 2mm of length, slightly decreases efficiency but makes it much more reliable over time.
i mean, why stop at three finns? as i understood it, the more the better
by making the flaps longer you gain a certain amount of built-in wear resistance
the flaps may wear down, but they have to grind through the whole extra length of the flap....
longer flaps means mroe durability, but also more friction, right?
@@Kram1032 as long as they aren't so long that the cross section of material touching the wall increases, it shouldn't be much more.
however, if the flap is too long or thin then then it will overcome the strength of the teflon, sag and drag excessively along the wall
You should make an radial lip seal that closes in the axial direction towards the bearing as part of the front of the transparent housing behind the bearing. Or an axial shaft seal. .
Or just fit a regular old oil seal there like all vane motors have had for the last 100 years or so.
1) Optimize Air Intake Quality: Ensure the air entering the engine is clean and dry. Contaminants can increase wear and reduce efficiency. Implementing effective filtration systems can help maintain air quality.
2)Refine Flap Design: Possibly making them like an aerofoil like a propeller would to help efficient movement of air, rather than just a flat wall. An increasing it back to three would help regulate even pressure better (i guess more like a capacitor discharging to allow smoother flow of electricity).
3)Alternative Materials: Consider materials like graphite composites or ceramics, which offer excellent low-friction properties and higher wear resistance. Maybe make the bearings ceramic? and coat the chamber in a graphite composite.
4) Heat resistant coatings? Maybe leakage increases over time as temperature rises inside causing expansion between parts. Possibly the use of gaskets would help.
Really enjoyed this video, that was recommended to me. You have yourself a new subscriber
Finally, another upload from you!
You can try with different propellors with other sizes and angles as the optimum propeller is different for each type of engine.
Springs? Why not magnets??? 6:00
Because springs are better
Lighter and provide more force
Why not air pressure?
@@jmsterdam wasting air
Won't worry at that speed
There are ball bearings so that doesn’t work
Absolutely love watching you develop these! Couple thoughts I had:
1. Are you still using some lube with Teflon? Can't hurt right?
2. I think the compression/pressure goes down with travel. So, I think going back to more flaps would be better. Would love to know if this works!
Tomatoes are disgusting!
If you keep if named flappy valve it should probably resemble flappy bird!
Could you replace the vane system with a compliant mechanism?
For optimization:
I think you can change the expansion chamber to be more round and have a better flow profile. Second, you could adjust the volume of the expansion chamber. Third, adjust the amount of flaps. Optimizing these could produce a higher rpm and longer run time.
3:20 that poor bearing not even able to do it's job.
Could you use magnets to connect the rotor and propeller? You'd eliminate the bearing leaks, and the additional weight may act as a flywheel
Nice idea! Have a back half and a front half. Front half would just be a front bearing and crankshaft to the propeller. Connect the two rotating parts via magnets. The issue would be you'ld want strong enough magnets to keep the parts connected but not so strong they tried to clamp together causing friction.
I want to say no, that won't work but I can't think of any reason it wouldn't that couldn't be overcome with some clever design. At least for very low power applications like this. Yeah, I can think of several things that would prevent the motor working but they are all things that could be solved easily. Nice idea.
I gotta say, that was a super creative way to approach that problem. I’m curious how well the flaps would handle bending fatigue over time but overall really ingenious.
you could probably get more rpm if you added a few more flaps and measure at what point the amount of friction from more flaps decreases the efficiency. Great idea though and beautifull you made it work.