@@Javii96right? I totally thought he was gonna be a brown guy! 😂 😂 now I wanna know what his accent is because I've only heard similar from brown guys, like its messing with my head
David Beckham- good looks -squeeky voice. You accomplished 3d printing engineer and good looks. I can only imagine you must be hiding a terrible secret.
For someone who speaks a 2nd language, your english dialogue is one of the greatest explanations I've ever heard on any kind of video.. I like the way you talk
This is what happened. The ball bearings heat on operation causing the walls to deform on each iteration the ball bearings will be wobbly and that cause your design to fail. You need to add a layer of heat resistant material that hold and dissipate the heat of those areas where you interact with ball bearings. Another topic is to clamp properly the 2 parts together and seal them properly and you will increase your success. Great work so far keep it up.
Dude, you look absolutely different from what I imagined! 😂 But it's nice to finally meet you! 😊 Fantastic work as usual!!! Stay safe there with your family! 🖖😊
Regarding the airflow: When I designed my turbopump that was one of my challenges (the pathway of the air) it's preferable if you do it tangentially. Also, the leakage problem exists when you use PLA!! Everything must be water tight in order to make it work properly, that's why you couldn't pop the ballons up. And to be honest, on your previous designs, I think that was also part of the issue..! With 600W power I can "propell" water at about 3 metres, the thing was design to operate at 3kW but since it's a 3D printed device, I seriously doubt it won't blow up once I apply that much power, but as proof of concept, yeah, it worked! :) Try to use CF Turbo (they do have a demo version) to design your props, believe me, once you get the hang on that thing it's just marvelous! Ah! Another thing, add a pressure gauge to the exit to measure the output pressure!
Love seeing the things you make with 3D printing. I just love the iterative process, of finding slightly better and better ways to make something more efficient. and 3D printing lets regular people do awesome stuff like this, without 10's of thousands of dollars worth of machinery, and thousands of dollars in material. 3D printing is such a learning and teaching tool, since it lets a regular person design and print something fairly quickly, test it, and make changes, all in their own house. Can't wait to see what else you come up with!
What most fascinating about stuff like this is seeing up and coming engineers being able to make things they've thought of in the comfort of their own home with these printers. Now imagine if you just take these are then make scalable models with CNC metal parts. You quite literally have just made a jet engine. Saving the R&D costs of multi-billion dollar companies. It's now in the hands of the "average everyday" person. Absolutely brilliant.
Modern tech has brought back the basement tinkerer back into a viable path for inventors. That was the standard for centuries, and the industrial revolution shoved the individual into a corner to do niche things. But what technology undid, it also re-did, and here we are. Ain't it cool?
Woo! So excited to see the balloon pop in the intro. Nicely done. It's amazing to see the progress you've made since I started watching your stuff a couple years ago.
Love it can't count how many times I've tried explaining to people on you tube trying to 3d print turbo's about volute casings. Being as that's where the pressure comes from and how it increases volumetric efficiency through fluidic coupling or entrainment if you prefer.
Good job. For the leakage problem between two printed halfes I use sandpaper on a glasplate to get both halfes as smooth and plane as possible (180 Grid and some water). Then I use some grease ( e.g. white petrolatum). Works well with PLA.
Your intake should be larger than your second stage. You're speeding up the air then expanding it across the second stage. These machines work with tolerances that are very tight and having the stages in the wrong order can wreck the machine due to vibration. 20+ years operating and working on these and i still learn more all the time.
If I'm not mistaken it looks like there's no point in having two stages. If they both have the same (or similar) sized intakes and operate at the same speed (same shaft) and also have similar outlet sizes then how is there a compounded compression. My understanding is that the compressed air from the first stage will expand to fill the volume of the second stage inlet and be back to almost atmospheric pressure. Great video and I'd love to hear your opinion on this
Looking at the stages, based on a visual assessment of the compressor wheels, it looks like he's got 2 different gas volumes there. I'm not sure how different, but they definitely look to be, also different angle on the blades. Not sure how that affects it either.
If the impedance (output cross-section) is mismatched he could be getting no real increase, sure. However I think he is still getting an increase. The ideal airflow or air velocity can be different at the same rpm because of the impeller geometry. Even two impellers of the same geometry could produce a static pressure increase I believe, but not as efficiently. You could of course put pressure transducers in each stage to verify this.
An interesting test would be to remove one impeller to see if it makes any difference to the time it takes to explode a balloon. One base line test would be to use your compressor directly attached to a balloon to time it.
@@nachgebaut4176I think because the flywheels were too far away and the motors were slow. Unfortunately I would need to redesign the entire gun and i kinda dont have time for this.
6:55 Instead of your plastic seals, you should have put seals cut from the inner tube, it's much more efficient and it saves you from using glue. In addition, your joints must be the full height of your air compressor.
A check valve on your outlet will help as the back-pressure is probably causing movement in your shaft and some resistance. Also like turbos etc you need very low tolerance gaps between your impellers and casing (cheap method could be to use something like aluminum tape on the casing or possibly seals on the blades from a soft material) - Either way super cool, my 3d printer gets hardly used cause i suck at CAD so i just draw things and make them other ways lol
a little wear is not a bad thing. What that means is that you don't have a lot of leakage in that area. Ideally it wears say 0.01" and then just rotates freely
There are real world applications: two-stage turbochargers. They use exhaust pressure of an internal combustion engine in place of compressed air, but otherwise operate this way. Normally, turbo chargers are just a single stage, but there are some two-stage ones out there. Very cool build!
@@TommyApel Yeah, compound turbos are crazy, but they aren't really useful for anything besides diesel because air-fuel ratios and pre-detonation issues with normal gasoline. Too bad the only diesels popular in America are the big boat anchor truck engines like Cummins and Duramax. It'd be nice to see more 4-cylinder turbo diesels.
The problem with that compressor being chewed up is either something where the shaft is off alignment by a hair, there's flex somewhere once it's in motion, or in some cases plastic parts like that will expand a bit if they spin fast enough. Might be neat to see something like this go further into making a rudimentary gas turbine engine, but it'd have to go into green sand or lost PLA casting processes with machining to clean up and balance parts. No way to get around working with metal, once you start dealing with heat engines. Also at that point you'd have to find a way to lubricate the bearings too, because heat and sealed bearings tend to not get along.
I'm not sure if you know this, but rotors like these, with a flat bottom, and that suck air from the top, have a net force pulling them axially "up" or out of the intake, because of the pressure difference between the plate at the bottom and the impeller at the top of the rotor.
What a cool build! My guess as to why the first stage showed more wear: This is the only impeller that is only supported by a bearing on one end, not both. As a result, I think it could wobble and shake more, causing it to hit the walls. It might be worthwhile to try to balance the impellers with weights or drilling holes. I believe this could be very beneficial to the efficiency!
A lot of jet engines are started with compressed air from another jet engine, the apu, or compressed air tanks. So your design does have a real world analog
Add a combustion chamber and turn this into an actual jet engine! I wanted to 3D print one that ran on ISO alcohol, but lost motivation half way through. Even if it runs on its own for ten seconds before it melts, that's a win!!!
Really cool build! For the gas turbine, wouldn't it be better to use a pelton type? And for the compressor side you need to consider volume, if the gas can expand again you will loose efficiency.
This is really interesting. Thanks for the video. Here are some possible improvements and explanations of the phenomina at play: First of all, it appears that you dont have a designated fixed bearing. So when standing up, there is some metal to plastic contact from the couplers or even some plastic to plastic contact in the turbine, which increases friction. Secondly, the reason why the first impeller got shaved and gradually got more play, is either unbalance or an aeroelastic phenomena, where the turbine gets pushed of center by the aerodynamic forces. It could be a feedback loop between the play thats already in the system (due to it beeing mounted on the bottom, rather loosly, at a different height then the center of mass and the center of pressure) and an induced oscillation caused by the tighter side achieving higher pressures, which then pushes the compressor over to the other side - repeating the process. This would correlate with it getting worse faster after achieving higher pressures. To get rid of this phenomena, increase the stiffness of the coupling between the shaft and the compressor wheel. You could also mount it at the top and at the bottom. The second stage could be improved with a propper stator that realigns the airflow and corrects for induced rotation in the fluid. Since the second stage is rotating at the same rate and direction as the first stage this induced rotation reduces the bite the second stage has on the fluid significantly. Also as you found out, reducing leakage is key. So implementing a proper pressfit seal (printed from TPU) between the two halfes would help alot. As for all turbomachinery: tollerances are live. So the tighter the tolerances, the less the airleakage, the better. Maybe this helps if you decide to continue the project, or anyone interested.
we actually do have a use for these when powered by compressed air. pressure boosters. it's not something i'd recommend and piston boosters are generally better but i have actually made a 1:6 centrifugal booster. it made sense for the project but the deciliters per second it puts out makes me cry, even at 35 bar.
im not sure if the secound stage does anything because it looks like the gas exspands to its initial volume after the first stage, the first stage and the secound stage turbines should have differant sise outlets but they seem to be the same so i think only the last stage actually does anything
Thank you for putting in all this work and not hiding it behind a paywall. You're one of the good ones. If I had it I'd sub to patreon to support you but I'm sure others who have the money to help will! Meanwhile, liked and subbed here to help where I can. ❤😊
The impeller are rubbing the housing because the clearances are considering what is happening at 0rpm, when up to operating rpm the centrifugal forces would cause expansion axially. Automotive centrifugal compressors using aluminum alloys are stiffer(relative to plastic/resin). If you dont want to do the engineering work to figure it out you can just axially scale the model and test the new one.
I think you missed checking out normal turbochargers. For one, they have a beefy thrust bearing which you seem to have figured out. Second, dual-stage compressors are usually for high pressure, not really for large flow. The 2nd stage wheel is likely too large, or 1st not large enough. Third you need to seal between the inlet AND outlet for each stage, not just one large seal. Fourth, when spool-up isn't a big deal, a larger turbine outlet is better. They work off the expansion of the turbine air, not so much the paddle/pinwheel effect of air slamming into the inducer-side.
Theres a difference between your 2nd stage and turbine and the 1st stage which is likely causing the rubbing.. the first stage is unsupported while the other 2 have support on both ends. 1st stage is wobbling. Put a support above the intake and lengthen your rod.
so check this out... decrease the space between stage one and two, run an analysis to determine how to tune the cavity of the first stage. direct multi-stage, and harmonically driven compressor. cant wait to see more!
So this is basically like a compound turbocharger setup you'd see on a crazy modified diesel truck, except with a single turbine spinning both compressors. It'd be interesting to see how this sort of design would change the performance and efficiency of diesel engines compared to normal turbochargers.
maybe instead of burning stuff to get a volume increase you might inject LN2 into the airflow, which boils becoming N2, and that can then drive the turbine. to evaporate the LN2 a heat exchanger might be used.
The funny part is, if you remove the entire 'compressor' in the middle, the greatest efficiency is realized. Going directly from the shop compressor hose to the balloon. Just... LOL
Maybe look at using 3d printed TPU seal ring between all 4 outer housing parts. the TPU will compress against the walls and help keep everything sealed in, so less air would leak out.
Nicely done ! But, such narrow air passages . I would add cross sectional area to the air passages to minimize resistance to flow. also, a thought: if you make a channel in the mating surfaces of the casing from one end to the other you could fit a seal made of polyurethane elastomer into it to seal the leak. Best of luck!
The balloon is not an indicator of how well it works. The more you restrict the outlet, the higher the pressure will be at the balloon; if you restrict the outlet fully, it would work at top efficiency going by the balloon measure. It only makes sense to use the balloon if you're driving the turbine with a motor, otherwise the balloon is just an indicator of the air pressure you put in, combined with the amount of resistance the air faces going to the outlet.
I love your videos. You will be one great engineer one day. Just be patient and think all over, a few times more. You should try printing some TPU to use as a gasket, instead of the hot glue. Polymaker TPU HF 95 prints flawless on the Bambu Labs X1C. Depending on the infill you can alter the rigidity. Hope this will give you some other perspective. Keep up with the great work!
It’s what I figured that the other parts were resin prints and the other parts were leaking compressed air . Probably reinforcing the larger prints with resin
Wow, pretty close to some rocket engine turbopump designs, but an impulse turbine to drive the shaft would get you better dP across than the reaction turbine you have now. You should consider adding an inducer to your pump inlet before the impeller for even better efficiency
Very cool!! Congratss!! Maybe the first impeler got damaged because the axial force from the system. Try to reduce the tolerances and add an axial bearing. You could add after the gas turbine.
My Theory: The only turbine that shows wear from eccentric rotation is the only one whose axis is not constrained by a bearing at each end. If you were to extend the shaft and incorporate a bearing at the inlet mouth, you might be able to eliminate that eccentricity. No need to reprint the housings necessarily either: You could adapt a bolt-on or clamp on or press fit bearing holder retrofit. As simple as a y-shaped thing, or even as fancy as the LAX air traffic control tower.
I think filling seams with silicone would have been much better as you would still leave an option to easily split the parts as long as one side had some light layer of wax or silicone grease to prevent it from sticking to one of the sides
I wonder if the curved in-path combined with the small diameter was creating drag inside as the air contacted the tube, creating boundary layer drag and vortices?
Great video, regarding the damage to the turbines (especially in the previous video) i have a hunch could be attributed to the perpendicular force generated by the turbines, in reaction to the compression action (a gyroscopic effect if i'm not mistaken). Placing them vertically was a great idea in-fact seems to do the trick, at least in most part. Hope this could be useful
Glad i said something useful, but actually i mixed 2 forces: the gyroscopic effect (which i think has the higher culprint) and the reaction to the compression by the air. I think you could analise the vectors in the project fase, and you could avoid the gyroscopic effect using an opposite rotation part that pull in the opposite direction. Although i fear would really complicate A LOT the project
Looks like the blades bent outwards at rpm, this could be a good thing for compression if they expand to an even closer tolerance, might require some lube tho
Not sure what the goal is here. Re-designing the wheel? Very cool print though! If you just want to blow up balloons. There is a much easier, more efficient way to do so. It's put the balloon directly over the end of your air compressor hose/ blowgun. It would most certainly take lots less air. I guess it's fun to play though! Or is it? I will give it a thumbs up for the effort in print skills. 👍
I can actually think of a use for a device like this. In the oil industry and in some other industries you have areas that can have potentially explosive atmospheres. Tools in these areas need to have very strict control over ignition sources, and therefore electric equipment becomes very heavy and expensive. As a result, compressed air is very common, and used to drive all kinds of tools. It's almost universally 90PSI/6Bar. So uf tou need a higher pressure a compressed air driven air compressor actually makes sense.
If I’m not mistaken, this is the first time we’ve seen your face, it like to see that build video!
when the video started I was like 'who the hell is that?'
@@TuttleScott i knew it was beethovens estonian cousin right away
Dude he looks so different than i expected😂
@@Javii96right? I totally thought he was gonna be a brown guy! 😂 😂 now I wanna know what his accent is because I've only heard similar from brown guys, like its messing with my head
@@forbiddenera😂 i thought he would look more like the guy that electrocutes himself in all his videos, i know you know who i’m talking about
David Beckham- good looks -squeeky voice. You accomplished 3d printing engineer and good looks. I can only imagine you must be hiding a terrible secret.
lol
💀
the balloon was such a formidable foe, he decided to face reveal after defeating it
For someone who speaks a 2nd language, your english dialogue is one of the greatest explanations I've ever heard on any kind of video.. I like the way you talk
This is what happened. The ball bearings heat on operation causing the walls to deform on each iteration the ball bearings will be wobbly and that cause your design to fail. You need to add a layer of heat resistant material that hold and dissipate the heat of those areas where you interact with ball bearings. Another topic is to clamp properly the 2 parts together and seal them properly and you will increase your success. Great work so far keep it up.
You can cool plastic near bearings with the air by making air channel insude plastic.
The handsome devil himself!
This series has been a genuine pleasure to watch. Thanks so much for sharing!
Dude, you look absolutely different from what I imagined! 😂
But it's nice to finally meet you! 😊
Fantastic work as usual!!!
Stay safe there with your family! 🖖😊
Regarding the airflow: When I designed my turbopump that was one of my challenges (the pathway of the air) it's preferable if you do it tangentially.
Also, the leakage problem exists when you use PLA!! Everything must be water tight in order to make it work properly, that's why you couldn't pop the ballons up. And to be honest, on your previous designs, I think that was also part of the issue..!
With 600W power I can "propell" water at about 3 metres, the thing was design to operate at 3kW but since it's a 3D printed device, I seriously doubt it won't blow up once I apply that much power, but as proof of concept, yeah, it worked! :)
Try to use CF Turbo (they do have a demo version) to design your props, believe me, once you get the hang on that thing it's just marvelous!
Ah! Another thing, add a pressure gauge to the exit to measure the output pressure!
You can use some Orings gaskets rope to get some seal, you can buy it by meter and cut the necessary piece
Love seeing the things you make with 3D printing. I just love the iterative process, of finding slightly better and better ways to make something more efficient. and 3D printing lets regular people do awesome stuff like this, without 10's of thousands of dollars worth of machinery, and thousands of dollars in material. 3D printing is such a learning and teaching tool, since it lets a regular person design and print something fairly quickly, test it, and make changes, all in their own house.
Can't wait to see what else you come up with!
What most fascinating about stuff like this is seeing up and coming engineers being able to make things they've thought of in the comfort of their own home with these printers. Now imagine if you just take these are then make scalable models with CNC metal parts. You quite literally have just made a jet engine. Saving the R&D costs of multi-billion dollar companies. It's now in the hands of the "average everyday" person. Absolutely brilliant.
Modern tech has brought back the basement tinkerer back into a viable path for inventors. That was the standard for centuries, and the industrial revolution shoved the individual into a corner to do niche things. But what technology undid, it also re-did, and here we are. Ain't it cool?
Speaking of printers, does anyone know what printer he used?
@@viduraherath4008 a mix of SLA and FDM printing
Nice work, looks like you pushed resin/plastic to its tolerance levels. Anything better will require metal parts.
Woo! So excited to see the balloon pop in the intro. Nicely done. It's amazing to see the progress you've made since I started watching your stuff a couple years ago.
Love it can't count how many times I've tried explaining to people on you tube trying to 3d print turbo's about volute casings. Being as that's where the pressure comes from and how it increases volumetric efficiency through fluidic coupling or entrainment if you prefer.
Excellent work, my guy. Huge respect 🤯
Congrats! This has been such a fun project to see you adapt and evolve over time!
Good job. For the leakage problem between two printed halfes I use sandpaper on a glasplate to get both halfes as smooth and plane as possible (180 Grid and some water). Then I use some grease ( e.g. white petrolatum). Works well with PLA.
Your intake should be larger than your second stage. You're speeding up the air then expanding it across the second stage. These machines work with tolerances that are very tight and having the stages in the wrong order can wreck the machine due to vibration. 20+ years operating and working on these and i still learn more all the time.
If I'm not mistaken it looks like there's no point in having two stages. If they both have the same (or similar) sized intakes and operate at the same speed (same shaft) and also have similar outlet sizes then how is there a compounded compression. My understanding is that the compressed air from the first stage will expand to fill the volume of the second stage inlet and be back to almost atmospheric pressure. Great video and I'd love to hear your opinion on this
Looking at the stages, based on a visual assessment of the compressor wheels, it looks like he's got 2 different gas volumes there. I'm not sure how different, but they definitely look to be, also different angle on the blades. Not sure how that affects it either.
If the impedance (output cross-section) is mismatched he could be getting no real increase, sure. However I think he is still getting an increase. The ideal airflow or air velocity can be different at the same rpm because of the impeller geometry. Even two impellers of the same geometry could produce a static pressure increase I believe, but not as efficiently. You could of course put pressure transducers in each stage to verify this.
An interesting test would be to remove one impeller to see if it makes any difference to the time it takes to explode a balloon.
One base line test would be to use your compressor directly attached to a balloon to time it.
Congrats on the successful build. After all of this, i can't recall seeing you hook the balloon directly to the hose, as a control.
You say there's no applications, but this is pretty much a turbocharger
It took you 3 months? Damn it took me 3 months to make a nerf gun tht didnt even work😭
Why didn't it work my guy?
@@nachgebaut4176I think because the flywheels were too far away and the motors were slow. Unfortunately I would need to redesign the entire gun and i kinda dont have time for this.
Really enjoy the new video format! This is awesome!
6:55 Instead of your plastic seals, you should have put seals cut from the inner tube, it's much more efficient and it saves you from using glue. In addition, your joints must be the full height of your air compressor.
A check valve on your outlet will help as the back-pressure is probably causing movement in your shaft and some resistance. Also like turbos etc you need very low tolerance gaps between your impellers and casing (cheap method could be to use something like aluminum tape on the casing or possibly seals on the blades from a soft material)
- Either way super cool, my 3d printer gets hardly used cause i suck at CAD so i just draw things and make them other ways lol
Literally sounds like a mini jet engine before you fire off the ingiters
this is one of the coolest things ive ever seen. keep up all of your good work. youre incredible
a little wear is not a bad thing. What that means is that you don't have a lot of leakage in that area. Ideally it wears say 0.01" and then just rotates freely
I stand impressed. Well done
What are the velocity comparison between the air coming out of the air line, and the air coming out of the compressor?
There are real world applications: two-stage turbochargers. They use exhaust pressure of an internal combustion engine in place of compressed air, but otherwise operate this way. Normally, turbo chargers are just a single stage, but there are some two-stage ones out there. Very cool build!
most of the time you just pipe one turbo outlet to the inlet on the next so they run in sequence, make it a lot cheaper.
@@TommyApel Yeah, compound turbos are crazy, but they aren't really useful for anything besides diesel because air-fuel ratios and pre-detonation issues with normal gasoline. Too bad the only diesels popular in America are the big boat anchor truck engines like Cummins and Duramax. It'd be nice to see more 4-cylinder turbo diesels.
The problem with that compressor being chewed up is either something where the shaft is off alignment by a hair, there's flex somewhere once it's in motion, or in some cases plastic parts like that will expand a bit if they spin fast enough.
Might be neat to see something like this go further into making a rudimentary gas turbine engine, but it'd have to go into green sand or lost PLA casting processes with machining to clean up and balance parts. No way to get around working with metal, once you start dealing with heat engines. Also at that point you'd have to find a way to lubricate the bearings too, because heat and sealed bearings tend to not get along.
I'm not sure if you know this, but rotors like these, with a flat bottom, and that suck air from the top, have a net force pulling them axially "up" or out of the intake, because of the pressure difference between the plate at the bottom and the impeller at the top of the rotor.
so cool to see the progress and the result - keep it up !
What a cool build! My guess as to why the first stage showed more wear: This is the only impeller that is only supported by a bearing on one end, not both. As a result, I think it could wobble and shake more, causing it to hit the walls. It might be worthwhile to try to balance the impellers with weights or drilling holes. I believe this could be very beneficial to the efficiency!
Crikeys mate! Nice Haircut!
A lot of jet engines are started with compressed air from another jet engine, the apu, or compressed air tanks. So your design does have a real world analog
Well done! Love the new set up too - keep going!
Yes! Finally, the balloons are exploded!. Good job
Thats an impressive and insteresting design
Add a combustion chamber and turn this into an actual jet engine! I wanted to 3D print one that ran on ISO alcohol, but lost motivation half way through. Even if it runs on its own for ten seconds before it melts, that's a win!!!
Neat. I wouldn't have thought you could push 3D prints this far and I actually work with them.
Hey congrats! I knew you'd work it out!
I love it, very fun to watch. Keep it up, can’t wait to see what’s next!❤
Really cool build! For the gas turbine, wouldn't it be better to use a pelton type? And for the compressor side you need to consider volume, if the gas can expand again you will loose efficiency.
Wow, nice to see you!
I'd love to see this used in a fuel turbine application. Congratulations on this, it is an awesome accomplishment!
This is really interesting. Thanks for the video. Here are some possible improvements and explanations of the phenomina at play:
First of all, it appears that you dont have a designated fixed bearing. So when standing up, there is some metal to plastic contact from the couplers or even some plastic to plastic contact in the turbine, which increases friction.
Secondly, the reason why the first impeller got shaved and gradually got more play, is either unbalance or an aeroelastic phenomena, where the turbine gets pushed of center by the aerodynamic forces. It could be a feedback loop between the play thats already in the system (due to it beeing mounted on the bottom, rather loosly, at a different height then the center of mass and the center of pressure) and an induced oscillation caused by the tighter side achieving higher pressures, which then pushes the compressor over to the other side - repeating the process. This would correlate with it getting worse faster after achieving higher pressures. To get rid of this phenomena, increase the stiffness of the coupling between the shaft and the compressor wheel. You could also mount it at the top and at the bottom.
The second stage could be improved with a propper stator that realigns the airflow and corrects for induced rotation in the fluid. Since the second stage is rotating at the same rate and direction as the first stage this induced rotation reduces the bite the second stage has on the fluid significantly.
Also as you found out, reducing leakage is key. So implementing a proper pressfit seal (printed from TPU) between the two halfes would help alot.
As for all turbomachinery: tollerances are live. So the tighter the tolerances, the less the airleakage, the better.
Maybe this helps if you decide to continue the project, or anyone interested.
I love the build music!
There are compressed air based air compressors for using a high volume of low pressure to create a small amount of high compression air
Excellent video and fantastic choice of music man! 👏👏👏
The concept is great I think it can be adapted to be used as a replacement for compound turbos on diesel engines
we actually do have a use for these when powered by compressed air. pressure boosters.
it's not something i'd recommend and piston boosters are generally better but i have actually made a 1:6 centrifugal booster. it made sense for the project but the deciliters per second it puts out makes me cry, even at 35 bar.
im not sure if the secound stage does anything because it looks like the gas exspands to its initial volume after the first stage, the first stage and the secound stage turbines should have differant sise outlets but they seem to be the same so i think only the last stage actually does anything
Thank you for putting in all this work and not hiding it behind a paywall. You're one of the good ones. If I had it I'd sub to patreon to support you but I'm sure others who have the money to help will! Meanwhile, liked and subbed here to help where I can. ❤😊
The impeller are rubbing the housing because the clearances are considering what is happening at 0rpm, when up to operating rpm the centrifugal forces would cause expansion axially. Automotive centrifugal compressors using aluminum alloys are stiffer(relative to plastic/resin). If you dont want to do the engineering work to figure it out you can just axially scale the model and test the new one.
Face unveil, eh? Enjoy your videos. Your success is deserved :)
Thank You ;)
Those impellers were great 😎
I think you missed checking out normal turbochargers. For one, they have a beefy thrust bearing which you seem to have figured out. Second, dual-stage compressors are usually for high pressure, not really for large flow. The 2nd stage wheel is likely too large, or 1st not large enough. Third you need to seal between the inlet AND outlet for each stage, not just one large seal. Fourth, when spool-up isn't a big deal, a larger turbine outlet is better. They work off the expansion of the turbine air, not so much the paddle/pinwheel effect of air slamming into the inducer-side.
It looks beautiful, good sir
Theres a difference between your 2nd stage and turbine and the 1st stage which is likely causing the rubbing.. the first stage is unsupported while the other 2 have support on both ends. 1st stage is wobbling. Put a support above the intake and lengthen your rod.
so check this out... decrease the space between stage one and two, run an analysis to determine how to tune the cavity of the first stage. direct multi-stage, and harmonically driven compressor. cant wait to see more!
So this is basically like a compound turbocharger setup you'd see on a crazy modified diesel truck, except with a single turbine spinning both compressors. It'd be interesting to see how this sort of design would change the performance and efficiency of diesel engines compared to normal turbochargers.
Baloon Exploder 1000 is ready (almost)!
Congrats!
:)
Your hair looks great
maybe instead of burning stuff to get a volume increase you might inject LN2 into the airflow, which boils becoming N2, and that can then drive the turbine.
to evaporate the LN2 a heat exchanger might be used.
The funny part is, if you remove the entire 'compressor' in the middle, the greatest efficiency is realized. Going directly from the shop compressor hose to the balloon. Just... LOL
Maybe look at using 3d printed TPU seal ring between all 4 outer housing parts. the TPU will compress against the walls and help keep everything sealed in, so less air would leak out.
Now we got a face to the voice. OK for some reason I was thinking of an old guy with a beard. I got no idea why. BTW, your videos are awesome!!!!
Thank You!! :)
Nicely done ! But, such narrow air passages . I would add cross sectional area to the air passages to minimize resistance to flow. also, a thought: if you make a channel in the mating surfaces of the casing from one end to the other you could fit a seal made of polyurethane elastomer into it to seal the leak. Best of luck!
Even an audible difference in performance before and after sealing it. I was going to suggest sealing the joints.
The balloon is not an indicator of how well it works. The more you restrict the outlet, the higher the pressure will be at the balloon; if you restrict the outlet fully, it would work at top efficiency going by the balloon measure. It only makes sense to use the balloon if you're driving the turbine with a motor, otherwise the balloon is just an indicator of the air pressure you put in, combined with the amount of resistance the air faces going to the outlet.
I love your videos. You will be one great engineer one day. Just be patient and think all over, a few times more.
You should try printing some TPU to use as a gasket, instead of the hot glue. Polymaker TPU HF 95 prints flawless on the Bambu Labs X1C.
Depending on the infill you can alter the rigidity.
Hope this will give you some other perspective.
Keep up with the great work!
You could consider buying yourself a ball valve so you can just turn it off and on again without having to plug and unplug the air line.
It’s what I figured that the other parts were resin prints and the other parts were leaking compressed air . Probably reinforcing the larger prints with resin
Correct me if I am wrong, but is it the 1st time we are seeing Let's Print?
Also you look damn cool, I love your channel!
You are correct!
Wow, pretty close to some rocket engine turbopump designs, but an impulse turbine to drive the shaft would get you better dP across than the reaction turbine you have now. You should consider adding an inducer to your pump inlet before the impeller for even better efficiency
Could you test it as a heat energy recovery mechanism?
Use as a way to cool something else, and see if waste heat collected could help power?
Very nice small project. Imaging putting a rotary gear ratio. These impellers will explode.
Face reveal !!!!!🎉🎉🎉🎉🎉
Very cool!! Congratss!!
Maybe the first impeler got damaged because the axial force from the system. Try to reduce the tolerances and add an axial bearing. You could add after the gas turbine.
When is the vane pump coming? Definitely was one of my favorite 3d printed pumps I've created!
Awesome video as always!
now turn it into a turbo jet engine !!! it already has almost everything it needs to do that actually
Excellent work.
It's just a bummer that we still have to be limited on plastic printers...
My Theory: The only turbine that shows wear from eccentric rotation is the only one whose axis is not constrained by a bearing at each end. If you were to extend the shaft and incorporate a bearing at the inlet mouth, you might be able to eliminate that eccentricity. No need to reprint the housings necessarily either: You could adapt a bolt-on or clamp on or press fit bearing holder retrofit. As simple as a y-shaped thing, or even as fancy as the LAX air traffic control tower.
I think filling seams with silicone would have been much better as you would still leave an option to easily split the parts as long as one side had some light layer of wax or silicone grease to prevent it from sticking to one of the sides
I wonder if the curved in-path combined with the small diameter was creating drag inside as the air contacted the tube, creating boundary layer drag and vortices?
Great video, regarding the damage to the turbines (especially in the previous video) i have a hunch could be attributed to the perpendicular force generated by the turbines, in reaction to the compression action (a gyroscopic effect if i'm not mistaken). Placing them vertically was a great idea in-fact seems to do the trick, at least in most part. Hope this could be useful
Glad i said something useful, but actually i mixed 2 forces: the gyroscopic effect (which i think has the higher culprint) and the reaction to the compression by the air.
I think you could analise the vectors in the project fase, and you could avoid the gyroscopic effect using an opposite rotation part that pull in the opposite direction. Although i fear would really complicate A LOT the project
It seemed like the shaft rotation had resistance. Have you considered floating bearings? Or even better, air bearings!
This is so GOOD! 👍👍
Great job!
Looks like the blades bent outwards at rpm, this could be a good thing for compression if they expand to an even closer tolerance, might require some lube tho
Not sure what the goal is here. Re-designing the wheel? Very cool print though!
If you just want to blow up balloons. There is a much easier, more efficient way to do so. It's put the balloon directly over the end of your air compressor hose/ blowgun. It would most certainly take lots less air.
I guess it's fun to play though! Or is it?
I will give it a thumbs up for the effort in print skills. 👍
You should measure the pressure tho
I can actually think of a use for a device like this. In the oil industry and in some other industries you have areas that can have potentially explosive atmospheres. Tools in these areas need to have very strict control over ignition sources, and therefore electric equipment becomes very heavy and expensive. As a result, compressed air is very common, and used to drive all kinds of tools. It's almost universally 90PSI/6Bar. So uf tou need a higher pressure a compressed air driven air compressor actually makes sense.
Great video. Do you think it's possible that you may be getting some slipping on the set screws on the shaft?
Can we see a rate of balloon expansion compared to just putting the balloon on the end of the air compressor hose?
1st stage only had one support bearing. if you desing a support on top of the 1st stage it will not wobble.
Just an observation, I wonder how well it would perform if you made the both impeller and turbine like turbo's impeller and turbine?