Opposed engines are better?
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- Опубликовано: 5 сен 2024
- Well if you losing your head is better, then I suppose...
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The Commer TS 3 was a success. They had developed a TS 4. Dodge stopped useing them when the bought out Commer so they could use their own engines.
Well the Yanks in the car industry have always been a bit lost when it comes to engine development.
Commer TS3 was a 2 stroke, 3 opposed piston, cylinder, scavenging supercharger engine, but used a single crank. About 24kw/l.
would've lasted longer if it wasnt restricted by design to it's initial horsepower rating, modularity and cost. cool as cucumber though.
Top video Matt, a clear demonstration that engineering is the art of compromise, the trick is finding the best compromise for the application
It better have oil injection like the Cummins ACE OP 2 stroke and Rotax 850 Etec turbo R.
achates does EXACTLY what I mentioned before- they make BOTH piston faces concave & polished- this reflects the heat away from the pistons & focuses it on the combustion pocket between the two pistons- making the combustion even more efficient.
"concave & polished- this reflects the heat away from the pistons & focuses it on the combustion pocket between the two pistons- making the combustion even more efficient."
- What? You do realise this makes NO sense. I'll prove it to you starting with 1 question. What forces a piston down a bore?
Ok so the polished piston faces reflect the EMP from the combustion and help with efficiency!
uummm.. .no. the explosion creates infrared heat, which gets focused back- but yah- same idea- just not with emp. ther is no emp. @@jlo13800
@@dirtygarageguy Pressure, not heat.
That's not what they said. And it's certainly nothing to do with EMPs
The advantages of an opposed piston engine are more-or-less two-fold. Firstly, the bore/total stroke ratio can be made extreme relative to the stroke travel of each piston and therefore the surface/volume ratio of the combustion chamber can be made much lower, leaking less combustion heat to the environment and allowing more work to be recovered from the gas. Secondly, because the stroke is, in effect, split in two, the length of the conrod can also be much shorter - half, effectively. If you try to package a single piston engine with the equivalent bore-stroke ratio to an OP engine, you'll find your bore/stroke ratio will be limited by the conrod clouting the bottom of the bore unless you resort to an infeasibly long conrod or move to a cross-head design, which is also very long/tall and then suffers from a poor conrod/stroke ratio increasing second order vibration forces.
For a 4 stroke you would need sleeve valves
I'm wondering if any one tried this type of layout with steam.
For a range extender use a cross shaft with the rotor for the generator mounted on it. Drive the cross shaft via hypoid bevel gears.
Can't really talk opposed piston without talking about Achates power. They are the ones that are actually developing, manufacturing and making them to compete with other engines. They are in a position of way more credibility than any other alternative engine design house I know of. If reports are to be believed, they have secured US military contract for powering Bradley Fighting Vehicles. They have also retrofitted an opposed piston engine to an F150 with similar performance of the V6 ecoboost, but 10% more gas mileage.
It is really complicated, it is both turbocharged and supercharged, has EGR (to aid gasoline compression ignition) and what not. Its understandable that they need all that engineering for the efficiency gains, because the era of easy gains through design improvements has long passed.
Any diesel is >10% more efficient than petrol Ecoboost, which has BSFC >240 g/kWh at its best, diesels have
@@My-Opinion-Doesnt-Matter hard to quantity the efficiency improvements in a single number, so I will just link to the article www.greencarcongress.com/2017/01/20170113-achates.html
It's not hard, it's simple: how much fuel engine consumes to produce a kWh of energy = brake-specific fuel consumption (BSFC)
en.wikipedia.org/wiki/Brake-specific_fuel_consumption
Of course it depends of engine rpm and load, so the best number is chosen to calculate the best engine efficiency.
We can calculate the engine efficiency by this formula (I simplefied it a bit):
1/(BSFC × 0.012)
So if the engine's best consumption is 250 g/kWh, then the efficiency is:
1/(250 x 0.012) = 33 %
For 200 g/kWh it's:
1/(200 x 0.012) = 42 %
All other methods (MPG, km/L, L/100km...) are vehicle specific, so the same engine don't have the same consumption numbers on a small city car, and a large SUV, so a BSFC is a lot better way to show engine's consumption and efficiency.
@@My-Opinion-Doesnt-Matter I think his point was that as a practical matter in most applications, efficiency is a map not a single point.
the bradley fighting vehicle is NOW in production.. .WITH an achates engine, built by CUMMINS... NOT A TEST ENGINE- NOT A PROTOTYPE- A PRODUCTION ENGINE, BY CUMMINS, DESIGNED BY ACHATES. done deal.
Great video, but I think you are missing some of the advantage of the OP engine and have a few misconceptions.
As for power density, they are running a 2 stroke cycle which does improve power. If we totally disregard this, they stil have a second piston and crank replacing the volume of a cylinder head. Of corse the cylinder head won't add much displacement on a conventional engine, but the second piston and crank will add displacement. Because of this an opposed piston engine with the same piston and crank may be 25% larger, but will have 2x greater displacement.
Next, you are able to entirely get rid of the valve train. This is nice because on the majority of engines, the valve train wears faster and requires more maintenance than the bottom end of an engine. Additionally the valvetrain tends to be one of the most complex and manufactring intensive part of the engine. So an OP engine could very well reduce the overall maintenance, complexity, and production cost.
I also think you may have a few misconceptions about the effects that the 2 stroke cycle will have on the engines. Traditional 2-stroke engines rely on crank case pumping to get fuel/air in the cylinder. Crank case pumping on its own is only about 75% efficient at scavenging. For this reason traditional 2 stroke engines rely on other thinks like expansion chambers, tuned ports, tuned intakes, etc to improve that scavenging efficiency. Sadly all of these listed items must be tuned to a specific rpm range to work and in turn give 2 stroke engines their classic powerband. The OP engine has a supercharger which is not limited in scavenging efficiency so they doesn't rely on any of these tuning effects. So if you look at real world OP engines such as the Junkers Jumo 205 engine and the Achates engines, they all have extremely wide powerbands with high peak power and phenomenal torque over the entire power range.
Sorry for the rant. I do love watching your videos, but I think I have a slighly different view on OP engines.
"As for power density, they are running a 2 stroke cycle which does improve power. If we totally disregard this, they stil have a second piston and crank replacing the volume of a cylinder head."
- In a world of emissions, using double the fuel isn't good.
"Next, you are able to entirely get rid of the valve train. This is nice because on the majority of engines, the valve train wears faster and requires more maintenance than the bottom end of an engine. Additionally the valvetrain tends to be one of the most complex and manufactring intensive part of the engine. So an OP engine could very well reduce the overall maintenance, complexity, and production cost."
- Almsot the same answer. Emissions. Valves are adaptable and hence why nearly all new systems use some form of VVTI etc.
"The OP engine has a supercharger which is not limited in scavenging efficiency so they doesn't rely on any of these tuning effects."
- so we're taking away the heads and removing our valve control ability and replacing it with a supercharger, which isn't helping with emissions and we still have pumping loses etc. Put in a simple way, in the current/past 30 year climate 4 strokes can't be beat on emissions vs power (efficiency) The 2 stroke cycles with cylinder ports provides little avenues for control.
@@dirtygarageguy Wrongo Mate, you need to study Achates. Better or equal on emissions and much better on fuel.
Think about it scavenging is not free in any engine. Half the motion and a lot of power in a four stroke is wasted doing it. Especially considering the torturous pathway and tiny valve curtain areas that 4-S must breathe through. Ever notice that big industrial air compressors use screw type blowers not reciprocating compressors, it’s because blower move air more efficiently.
So the externally scavenged engine has many advantages and efficiencies. It breathes through large Efficient airways. The prime mover of air is more efficient and can be optimized independently from engine rpm. Throttle plates, waste gates, CVT and fixed multi ratio drives can be used, again demonstrated with measured results by Achates.
20:42
Granted most of this is just a thought experiment for me, but this is the direction I've been leaning lately. I'm nowhere near doing a project car, let alone manufacturing, but figure up how much ass is required to accelerate a vehicle and select an electric drive motor based on that. Work backwards from that point to determine what size generator, battery/capacitor bank can share that load during max acceleration, and charge the batteries/caps during idle & cruise. Select the generator then you can select an engine to drive it. If it's a constant rpm generator, you can use an engine tuned to that rpm band for maximum efficiency.
This is a thought experiment for me as well but I was learning towards the Cyclone Power Technology’s external combustion closed cycle steam engine as a range extender. Since I started looking into OPOC engines of late, I am not so sure.
These thin connecting rods in this configuration are stretch loaded where in traditional configuration connecting rods are compression loaded. So they could work being this thin.
What about the advantage of the pressure of the combustion chamber only acting on the pistons and not being wasted on the cylinder head. i.e. for every force you have an equal and opposite reaction so all the forces will be used to turn the crankshafts so the efficiency will be enhanced?
The head would have to move in order to waste energy. The formula for work done is W=Fs where F is the force and s is the distance of displacement and ideally the piston will move down without the engine moving up at all (which isn't exactly what happens because engines do vibrate) so even though pressure is being applied to the head there's no work being done on it.
What stuart said. For instance, blowing up a balloon. Work is required to force air into a deflated balloon, but once the air is in the balloon, no work is done keeping the balloon inflated.
@@BuffMyRadius I see your point about the work. The work done is double as the other piston also moves. So this would be the same if the single piston had double the stroke length. I wonder what the reason for the enhanced efficiency is? 🤔
@@gbone7581 My guess would be that the opposed piston configuration can run large expansion ratios without absurdly long crank throws. There's probably something else about flame front propagation and lower piston speeds in gas engines, but most of these opposed engines are diesels.
It was called British Rail, you cheeky young tyke.
Lol I know lol I used to work for NRS in york.
Hudson Hossak 2 stroke opoc.
Get on with it Matt, have it on my desk by end of play Friday 🤣
Isnt an advantage of the opposed pistons that you can have a perfect combustion chamber? and that you have twice the stroke.
Perfect? And twice the stroke, for twice the fuel and air...
What puts the OP engine ahead of all other layouts is that it doesn't require a valvetrain, or cylinder heads of any kind, as well as omitting the use of camshafts. Despite looking more complex on appearance actually is much simpler in design elements because of said exclusion of camshafts and valvetrain and heads.
Naturally then, an opposed piston engine would require more noble components, perhaps niobium, redirecting the hot gas to the exhaust, being more reflective on the infrared. That being said, would it be possible to reuse that energy on a stirling, running a hybrid, for instance? One can run the exhaust on one side of the stirling, and intake air on the other... Considering the Throttle problem... CVT anyone? Would like your input in this, I plan to tinker on a opposed piston design in the future.
Also, what about natural gas? The better the compression, the more attractive natural gas becomes as a fuel...
look up achates power & cummins- specifically their advanced combat engine- ALREADY IN PRODUCTION... NOW. all those problems? solved.
So the reflection on the polished pistons refocuses the electromagnet energy back in the chamber for more effieint oomph.
@@jaybee3165 We hear about those but no specifics. Only that Achates is producing them. Nobody's buying either. I'm curious, but I doesn't seem to be boding well for them.
@@ZetoBlackproject ford motor has an F150 test bed that achates built at ford's request, but ford will probably go all in electric. the U.S. military already has a contract with cummins to build an achates 1000hp opposed engine- production models are already tested & running- so someone IS buying. I could see achates being a smash hit success as an aviation engine- the very place where these engines came from in the first place- the jumo, still to this day holds the most efficient burn rate per hour of ANY aircraft- and with extreme reliability. an engine like that SHOULD have been on EVERYONE'S radar straight out of ww2... only 1 thing would explain their lack of dominance- I smell a big oil rat. my prediction? after tesla finishes taking a wrecking ball to APi & opec's monopoly? we'll see a ton of innovation on a huge wave- ethanol, opposed piston and a whole host of other innovations.
@@ZetoBlackproject also- achates only produced the prototype for ford's F150 platform & for a Peterbilt 579 truck with an achates engine.
the military contract is an achates engine design that is built by cummins for the military- that's a done deal- bradleys & troop transports will be the recipients.
my guess? you'll see them in Peterbilts too. walmart is already testing one.
most people fail to understand- you & I look at an engine like this and think: "WOW! 30% better mileage, I want one.
put yourself in big oil's shoes: what THEY hear is? "30% loss in sales!"
... and when you have $4.5 trillion a year to buy federal agencies, finance election campaigns, fund media wars- all they'd have to do is call up ford's CEO & say- "you take this engine to production & you can consider yourself bankrupt".
Look at Achates opposed piston engine.
Could work if they added freevalve 🤔
Bit of Super Slip to keep everything humming
the moving work boundary is double. so work extraction is double. to it is more efficient.
And double the cranks, pistons and rods... but has poor porting and valve timing is none existent
@@dirtygarageguy watch?v=8qmAlnIh4mk
There was also a super pumper for big fires in New York City, NY and is now in a fire engine museum in Michigan !
I think you're missing the benefit of the system. You're doubling your stroke length without increasing piston speeds. This means you can have astronomic expansion ratios.
Yeah I agree. The extra crank and extra pistons and extra casing etc doesn't make any difference...
Funny that the people who fool around with this design never seem to use that as a benefit...
They still use a Class 55 Deltic for Freightliner (container trains) work as no modern diesel electric locomotive can equal it for hauling power.
Napier Sabre produced some great (sounding) engines, other than the Deltic, including the twin crankshaft H Block aero engines used on the Hawker Typhoon & Hawker Tempest fighters in WW2.
How about making a mini deltic 2 stroke out of 3 60 deg v6 mercury optimax 3.2 L 3160 cc outboard bigblocks. this will give 9480 cc or about 578 CID of 2 stroke madness.
Them deltics were awesome. Now take 3 60 deg mercury optimax 3.2L 193 CID 2 stroke blocks to make a nice 578 CID mini 2 stroke optimax deltic!
Doxford and Burmiester and wain did it quite successfully as single crankshaft engines
Sur le moteur OPOC il faut diviser la course les pistons par deux pour avoir la même cylindrée que le moteur
classique 4 temps ou considérer 2 cylindres pour celui-ci.
Le balayage sur l' OPOC est de type uniflow qui permet un meilleur rendement.
On the OPOC engine, the stroke of the pistons must be divided by two to have the same displacement as the engine
classic 4-stroke or consider 2-cylinder for this one.
The sweep on the OPOC is of the uniflow type which allows better efficiency.
I think you have made a mistake in your comparison; in order for it to be an equivalent comparison the example on the left should be TWO cylinders
That Deltic animation has just given me a stroke.
They got a wicked cutaway at the National Train Museum in York, England. I was lucky enough to stop there when on a trip to the UK.
Probably a 2-stroke, haha!
@@timduncan8450 My 2 stroke just gives me bills 😁
So archates has the best truck engine?
mart.cummins.com/imagelibrary/data/assetfiles/0058689.pdf
One little quibble: Most of the designs I have seen for opposed piston engines are NOT naturally aspirated, either a supercharger or a turbocharger are set up to eliminate the throttle and remove pumping losses. With either system they can very accurately control air volume entering the cylinders, based on pressure and temperature. In addition the removal of the heads with their cams and valves also eliminates losses and increases power output. I do agree with you wholeheartedly, that naturally aspirated versions are shit. Variable exhausts and resonance tubes belong in the dust bin of history.
Here are some thoughts, More torque would have to be transmitted to the crackshaft during the first part of the combution stroke, as the combustion space is expanding twice as fast compared to the engine with a head. So either the flame propagation would have to be made faster(another fuel added to the diesel) or the crankshafts could be offset to the bore centreline to get a greater angle acting on the crankshaft closer to TDC on the combustion stroke. This would also improve efficiency in two ways. Reduced thrust loads of the piston skirt on the bore, and less combustion pressure lost as the ports start to open as more of the work has happened earlier in the stroke. Altenatively, much higher charge density(more boost) could be utilized to counteract the chamber volume change per degree of crankshaft rotation problem, but injection timing would have to be very late.
Pressure is related to volume, so as volume increases, pressure drops.
Pistons are pushed down, not pulled down.
Desaxing. The cylinders increase loading on the upstroke.
@@dirtygarageguy Yes, i understand that, but wouldn't the cylinder pressure be less at 45deg ATDC on the opposed engine if both engines had the same displacement and compession ratio??
that works. there is also a Michel Opposed-Piston Engine that uses 3 pistons. It is arranged almost like the Mercedes Benz star badge emblem. Always wondered about those. Thanks for the great video.
That's the one with the combustion chamber in one of the pistons right
oldmachinepress.com/2014/02/24/michel-opposed-piston-diesel-engines/
Yes in deed. The crankless ones look a little sketchy to me.
@@mpetersen6 oh yeah thats the one!
Looks like it would make for a nice range extender for EVs. 3 small cylinders and 2 cranks coupled by 3 large gears with the center being the generator makes for a nice flywheel. Maybe even use this as a more efficient backup generator, built into your car no-less.
yes this would be nice all this OP 2 stroke would need is a quick top off of synthetic amsoil interceptor 2 stroke oil. XD-100 oil is cheaper at walmart and i run it in my 8v92 2 stroke now as it goes onsale at walmart.
Look up 5TDF engine, it's a 5-cylinder 10-piston diesel used in some Russian tanks.
But you probably know about it already.
2 stroke OP ukrainian tank engine 6TD-4
mart.cummins.com/imagelibrary/data/assetfiles/0058689.pdf
On your engine it shows the exhaust port and intake port open at the same time, do you think that would work. The German engine of world war two to work the cranks were slightly out of time so intake and exhaust would not be open at the same time this caused vibration but they used it anyway.
mmmm... actually the jumo was smooth as silk. all they did was make the 'meeting point' (half way) slightly favor the exhaust side. both pistons still had the same travel distance and timing, when left piston was at bottom center- so was right.
Matt, was there a reason you only went into details on opposed pistons where the crank angles were in sync? I seem to remember in Harry Riccardo's book, from many years ago, that the best design had the crank angles offset, which also altered the port timing quite favourably on a 2 stroke.
You want the exhaust port first to drop the pressure in the cylinder before opening the intake port. Otherwise you could get exhaust blowing back out the intake.
Jumo used 8deg intake lag, F- M and Achates use 12 degrees. Don’t recall this detail on Commer or Doxford , etc.
It would be nice to see an OP 2 stroke in snowmobiles. How about an OP 1700 rotax made from 2 850 etec!
The opoc engine at :06:48 can have the strokes of both pistons halved, for half the average piston speed , allowing higher max RPM, and since HP=Torque X RPM, the max HP will be higher, with a combined BDC volume equal to that of a full stroke single piston. The heat you worry about will only be in the cylinder half as long as that in a four stroke engine, as it exits at the bottom of each down stroke, rather than remaining until being pushed out on the up stroke.
Half the stroke is lower displacement. Less charge = less energy. Less energy = less torque. If we go with what you said about equal volume, you have 2 cranks, pistons and rods vs that single...
@@dirtygarageguy Half the stroke per piston, same combined stroke per pair, same torque per pair, higher maximum RPM due to half the swept area (half the piston speed) per piston, higher hp (Torque x RPM = HP.). Shorter rods reduce the per piston/rod mass, allowing higher RPM, so, higher HP
2 cranks... gearing to connect the 2. These engines have been built, show me one that revs to 20k rpm...
Also you seem to think piston speed matters, it doesn't. What matters is piston acceleration.
@@dirtygarageguy These engines have been built as diesels, with long strokes.
Have you ever heard of "hydro-diesel" fuel (80% diesel, 20% water and a catalyst), it basically remove the heat from the diesel engine and uses it to create power out of the vaporized water droplets.
Yes, ran this back in the mid 90s it wasn't that great power went down in propotion to water % increase and it was good at destroying pumps and injectors
@@TheBlibo no shit sherlock, water is only used as an intercooler to stuff more air in the cylinders
As 2 strokes are designed to be “on the pipe” or running their optimal rpm, could see these being very useful in today’s hybrids with the ecvt to direct any excess power to a generator to charge up batteries
2 strokes aren't designed to be on the pipe...
@@dirtygarageguy I mean “on the pipe” as a term we used in racing 2 stroke motorcycles. It’s the rpm range where the exhaust is in resonance and maximizes exhaust scavenging. It’s why I love the term “tuning”. Essentially the most efficient range for that engine, is determined by the geometry of the exhaust pipe.
There were also leyland L60 RR K60,& Coventry Climax H 30
Opposed pistons seem like a good option for petrol-electric hybrids.
One where the petrol engine drives an electric motor that can then distribute the power as needed from a small battery assembly.
Also is lubrication a problem i feel the exhaust port will collect oil from the piston and then emissions a problem
Read an SAE article that Achates achieves similar oil consumption rate as traditional 4 stoke engines. However, no detail as how they do it. If lubrication is not a problem, emission must be. If lub is not a problem and emission as well, the engine should have been in mass production and already on US trucks. Must be something.
@@catchnkill Dude, the States don't allow high mpg vehicles like the Volkswagen Blue Motion TDI vehicles to be imported over here, it's politically more complicated than that, European Countries will be A SHIT TON more likely to allow companies to mass produce them kinds of engines than over here.
In spite of these facts, I suspect something in the design is still being figured out...... unless they're working for military contracts to sell to military like that one green car congress web article talked about....
What about sleeve valve angines Matt?
What about them?
Thanks man, do you answer technical questions from comments?
Yes
@@dirtygarageguy so if I'm understanding you correctly. Opposed cylinder engines are not good when your fluctuating RPMs? Therefore they operate better as APU like in airplanes?
Would using the opposed diesel APU in EV be a viable option or are there also some shortcomings to that?
The car is propelled by electric morotrs but you can save weight by adding less batteries and charge with the APU
Opposed ported engines or ported engine in general aren't very efficient outside of their peak envelope.
Great Britain once made an opposed piston large marine engine called the Doxford; I think the design was patented in the 1870's, vertical direct opposed piston diesel, not the diesel you put in you car or heavy goods vehicles, heavy marine diesel with an SG close to 1.0 the fuel had to be heated prior to use.
These engines I studied at college however they were redundant before my career at sea began. The were still part of the curriculum? & I remember a fascinating large cut away working model of one in the Engineering School foyer.
My elder brother told me about sailing and maintenance on them in his career the 1970's when they were at the retirement stage and for a reason!
Lubrication and heat, opposing problems of that particular engine.... and as all good sea dits, (storys) there is an occupying song....
Sung to the beat of MacNamara's Band:
"Oh my name is William Doxford and I come from Sunder-land.
They say my diesel engine is the finest in the land.
The pistons bang, the cranks go clang and the camshafts grind away.
And you only have to oil the bug*er fifty times a day"....
They are not with us now due to factors that made opposed piston engines redundant.
Message ends apart from....
Hope you like the song, play the proper one first to get the feel.
If your from the " Good Ol US of A" and voted for Trump, just fuck-off!
'too many parts'? REALLY? have you SEEN a 4 cylinder engine in the average compact car? HUNDREDS OF MOVING PARTS. the jumo diesel STILL to this day holds the record for lowest fuel burn per hour of ANY aircraft engine- and that was WW2. they solved the heat issues by making all the high stressed components of stainless steel.
"'too many parts'? REALLY? have you SEEN a 4 cylinder engine in the average compact car?"
- Yes I have.
Is it possible to add large cylinder fins all over this OP engine design to dissipate the heat ?
Coolant is better than air cooling with fins. But heads are already cooled pretty much as good as you can
@@dirtygarageguy Right, thanks.
Instead of rattling on about uniflow needing superchargers, just simply say 2 strokes without crankcase scavenging require supercharger scavenging & move on. Of course this is why all direct injected 2 strokes are supercharged, well except for that Bimoto one which thus didn’t work & bankrupted them. Of course one can build a opposed piston engine where one end is a 2 stroke & the other engine is a 4 stroke running twice as fast. The 4 stroke does the scavenging while the 2 stroke does valving, but why not twin charge it anyway.
Amarc made an Opposed Piston crankcase charged 2 stroke diesel outboard. they came in 9.5 HP and 18.5 HP.
There is the Rotax 850 Etec turbo 2 stroke which is DFI, turbo and dry sump oiling with crankcase pumping.
The etec 2 stroke rotax uses the crankcase and turbo on the 850.
Is there an advantage in the longer stroke overall?
Longer stroke
@@dirtygarageguy LOL
Higher compression ratio and lower piston speed
@@catchnkill higher piston speed*
@@288gto7 You are correct that longer stroke with the same rpm. Piston speed is higher. However, this opposing piston design does have an advantage of lower piston speed. There are two pistons to cover the stroke. Each piston only travels half the stroke length. At the same rpm, the piston speed is 50% only comparing this OP design with traditional 4 stroke engines.
You can make ported engines throttle better by using a sleeve port arrangement. You can then vary the port size and timing on the fly
Yeah like a Boyesen exhaust trapping valve or a Crecy sleeve 2 stroke.
yeah like a rotax RAVE vallve or an exhaust trapping contouered to piston shape.
It’s inaccurate to call the blowers “superchargers”, they’re scavenging blowers on a two stroke engine. Supercharging only works on four stroke engines, six strokes too.
Wrong.
T64 use 5 cylinder inline opposed piston 2stroke diesel mainly for compact design and modular power pack that is easy to exchange quickly rather than the earlier t54-55/type69 regular V12 4stroke diesel.
interesting design the Russians used in these tanks.
Does ukraine have the TD op 2 stroke.
Most tanks used by Ukrainian armoured units are T72 same as Russia’s armoured units. T72 use a conventional 38L V12 Diesel engine as the T64 Tank was very expensive to produce compared to the T72
@@BentSpanner The ukraine 6TD4 OP 1800 HP 2 stroke is my favorite tank, better than the american crap anyday. I hate that gasoline turbine GE torqueless thingy.
@@BentSpanner ruclips.net/video/t6T4alWOGfQ/видео.html
@@jlo13800 OK I get you, that engine is in the German Leopard 2 tank. Germany has given these to Ukraine in their defensive efforts.
I think that single cylinder dual piston setup should be talked about more. I have never seen that design before. I feel confident that any heat issues could be worked out. One thing I did notice is that the design looks as if it would handle more expansive fuels as well. Seeing that the power cycle will be split between two pistons I would think the length of the stroke could determine fuel type and the efficiency of fuel combustion in relation to it's expansion.
CAN AND ALREADY HAVE BEEN WORKED OUT. look up 'achates power'. they have working test bed engines in ford F-150's & a 10 liter in a freight liner tractor trailer, actively hauling for walmart. how they solved the heat problem? pure genius. stainless steel pistons, both with a perfectly convex shape, polished, and focusing the heat on the combustion area. this reflects the heat away from the pistons. they're also porting oil pressure through ports that run through the piston. this maintains a nice even temperature in the pistons. also- cummins has officially adopted the new achates tech- and are ACTIVELY manufacturing the armie's new advanced combat vehicle engine with an achates design. not a test bed- A REAL WORKING, PRODUCTION ENGINE, with 1000hp in less space & less weight than the old engine it replaced- a 750 HP v8 diesel.
oh yeah... cummins & achates power- big tech meets 2 stroke diesel power. diesels will never be the same again.
How about a KX1000 OP 2 stroke dirtbike made from 2 KX500 engines. that would make one sick trail bike!
Thanks Matt, I've been asking for some comments about the deltic Napier engine. Already know a metric shitload more than I did before.
With OPOC engines, at a given power output, mean piston speeds are cut in half, relative to a non-OPOC engine of the same stroke number--and thus friction is reduced roughly 75%
I'm listening at 2x, but you still haven't mentioned it after 11 minutes. Edit: got all the way through the video and you never mentioned it. Hmmmm. Seems like a major miss for a supposed engine expert.
Tugboat and other marine diesel engines use OPOC configuration. The Ohio class submarines (I was a crew on USS Ohio in early 90's) have an OPOC Fairbanks-Morse making 13 MW surfaced and 12 MW submerged (power is reduced because of exhaust backpressure when running on snorkel at PD (periscope depth)).
I didn't mention it because its not true.
Hi Dirty Garage Guy, great videos! I started to believe the Omega engine scam and I'm glad your expertise & common sense was able to shine through the muck. I've also been curious about opposed two stroke diesels in this arrangement. It now seems like we have plenty of dials to turn to make this work better.
I take it that you are dubious about the Achates engine?
Not dubious, it works, just has a specific application. Some of their claims are a bit overblown though, specifically the efficiency numbers
Just seen that Cummins have just made 1000hp 4 cyl. opposed piston 2 stroke deisel for tanks. Might not fit a bike though.
mart.cummins.com/imagelibrary/data/assetfiles/0058689.pdf
How about a 1700 Rotax OP made from 2 850 Rotax Etec turbo 2 strokes, that would make a sick trail sled with turbo. Imagine a KX1000 OP 2 stroke dirt bike make out of 2 KX500 motors.
i'd be very interested to see what you think of radial engines
I love radial engines
yeah the Zoche 2 stroke radial diesel!
If we're buggering about with opposed pistons, how about free piston gas generators? No cranks at all...
Aaahh.. one of Manolis Pattakos gizmo's.. I think he eventually went fully overboard in a perpetuum mobile kind of way on the F1technical forum.. something with venturies and pushing them forward in the wind with turbines inside..
I imagine the perfect setup for this would be 2 x straight 6 pistons to an alternator or two.
How do these compare to a the LiquidPiston style of rotary or gas turbines? (In terms of a hybrid setup, driving an electric generator)
Hi, could you explain the difference between long and short conrod? xD
Yeah, ones longer lol
Well no shit X)
I wondered if it changes only wear or some other aspects
@@nx1552
The reason that one is longer is with only one crank it has to reach up to the second piston. Think of the outer pistons as movable junk heads. The outer pistons to me connected to the crank need really long rods or cross head arrangement like a steam engine or large industrial piston air compressor.
A few years back I saw a video on a free piston engine being used as a generator. That would be even less complex. No cranks, no rods.
@@nx1552 it also changes the peak piston velocity, as in with a longer rod you move from orange towards blue, ruclips.net/video/knndgVWAPsQ/видео.html
How the hell do they control oil from leaking past the rings when the cylinders are so high?
They use a “Trunk Piston” it is essentially a very tall (long skirt) piston with an extra oil control ring or two at the bottom. The lower ring pack never crosses the ports. So crank case is never connected to ports like in a weed eater type 2-stroke engine is.
@@timduncan8450 Still do not understand completely. How about the combustion chamber between the intake and exhaust port? How they lubricate that portion? Mix lub oil with diesel like normal two stroke motorbike engines?
@@catchnkill No oil in that area at all & no reason for lube on most of it. The pistons have “Top land” so the rings don’t touch the center portion of the Liner you are asking about.
@@catchnkill Oil metering to the intanke and a very clean burning synthetic 2 stroke oil. I heard these run well with amsoil interceptor 2T oil. I fill and run XD-100 oil inmy 2 stroke 8v92.
I think I see one engine. One engine and four piston. The phrase, "Opposed Pistons", might be appropriate. But "Opposed Engines"? No.
Actually if you can retain more heat and use less fuel producing less heat now you don’t have a problem. More efficient.
🤔👍 nice one Matt enjoying this stuff
Diesel electric is great if you're operating a mining truck, dragline shovel, or cargo ship. In mining trucks, the biggest recent increase in efficiency has come from autonomous mine operations. Komatsu claims their automation system increases mine productivity by 15%.
Cat eats Komatsu every day for lunch!
Show us p-V diagrams for each type and efficiency. Fluid engine?
Could it not use a sleeve valve on the exhaust to change the port timing?
Matt l’m sure this would work with Alfadan crank/rod arrangement 🤣🤣🤣
I think your right these OP designs will lend themselves to hybrid EV systems to generate energy for range extending or remote area charging while also covering 2 other EV downfalls heat/energy for storage of cabin heat systems and battery thermal management for cold weather applications. I seen something about heat pump systems going into some of these EV's but the cold weather is already taxing the batteries on these vehicles so a alternate source for heat and energy is a great idea. Fuels are still going to be produced for some time yet as we need them for many reasons and the byproducts of fuel production. The EV sticklers that are so hard core to be stuck on pure EV should have to travel to Alaska in the winter in their Tesla if they dont understand why we need focus on hybrid tech at this stage and progress to the pure EV in areas/locations/users where it is feasible. One thing you havent mentioned is how these 2 stoke designs you have been going over recently play out with alcohol type fuels and adds a question from me (non engineer), do these fuels not have more chamber cooling properties that could stabilize the thermal issues on these headless type engines at least partially negating the issues to a manageable level? sorry for the poor sentence structure my education was limited to swinging a tobacco cutter at 14 to support my family. I like the simplicity of the of the triangular design. I like that your tossing in the bits about resonant or pressure waves in the port and runner design/tuning i feel most people are unaware of what this is and the results of a modification to an engine due to this. For instance Dude puts large tube headers on small block and loses power or idle control at the red light due to huge cam, convertor, and dual plane intake.. swaps intake to single plane design gains back the power and idle control or something to that effect. Could be a good video topic. Might save someone from bolting on less HP one day lol..P.S i subbed you sorry i thought i had years back but i have subbed so many and use YT as my TV. I havent watched TV in about 12 years.
No chemical fuels or batteries are needed with overunity motor/generators that tap aetheric ZPE energy anywhere from space. Nikola Tesla, T Henry Moray and Bruce Depalma not to mention many others. I just dont see the hangup on chemical fuels. However a 2 stroke 850 Rotax Etec turbo ski doo is a lot of fun. OP 2 stroke should make it into snowmobiles soon. brapppp.
Yes alcohols burn cooler, have high octane, boost power and will help cool your 2 stroke pistons.
Oh yes alcohol has a cooling effect and just add some castor 927 maxima 2 stroke oil for that awesome stench. An alcholo fueld engine proppably runs cooler than them EV electric motors so it migh be hard to ride up in alaska with one.
What of the reduction in parts???
AND ! You have two times the surface on the pistons !
You are missing a very important feature.
You got 2 pistons moving opposed, so 1 piston only has to cocer half of the darn stroke. So you have half the avarage piston speed, and same goes for piston accelaretion. For a given rpm and stroke / bore vs a regular piston engine. It has less losses, you know that 0.5*m*v*v thing, having double the mass but half the speed means buisnes.
And thats where these things shine when you got them runnning. Allso pistons moving in exact pairs, it has better balance.
Wrong. Look at my example. Same speeds... if you have 2 pistons for the same volume as 1 cylinder then that really is stupid.
Absolutely not stupid. Yer 1 cylinder engine covers only 1 stroke length. The opposed one covers 2 stroke length. So its double the capacity.
Double the capacity, double the fuel, double the mass... 2 engines...
Minus the heads, like I said in the video
Come on now. Take a 100 ccm single cyl engine. Do it like you do on your video. You get 200ccm engine. Now down size that thing to 100ccm. You can half the stroke. So you get half the piston speed on avarage.
Plain simple.
Oooooor you can use half the bore area, and keep the long stroke. In witch case you get smaller mass. And in Both cases you get better balance.
Oooooor you can upscale the tiny 100ccm 1 cyl engine, but then you have issues with balance. Kay?
Maybe you can help this channel
Геннадий Кореневский
I think you have the enthusiasm to build two stroke engines. This channel posted videos of his own opposed piston engine like modified commer knocker engine and a video of a possible diesel split single "twingle" engine. He said he is a retired loner and couldn't build prototypes of his work anymore. Maybe you can. Looking forward that you will notice this comment. I'm from Philippines, he's from Russia.
Have you considered the commer knocker engine?
This is best and simplest opposed pistons engine construction
en.wikipedia.org/wiki/Opposed-piston_engine#/media/File:Simpson's_Balanced_2-Stroke_of_1914_high-res_animation.gif
Simplest?
19:57 would make a fantastic Zero Turn mower engine.
how about an opposed piston 2 stroke snowmobile, like an OP 1700 made from 2 Rotax 850 Etec turbo R engines.
Would Opposed engines be better for smaller garden tractors and hooked up a hydrostatic transmission.
Oh hell yeah! Now take 2 Rotax 850 Etec turbo engines and make a nice 1700 OP Rotax and lay it down in a trail sled.
Direct water injection would help with both efficiency and cooling.
@Paul Kargin Not to flood it. If it is dosed right to prevent overheating there is no condensation.
@@brankosumonja2048 You basically need to rig water injection to turn into dry steam to minimize lube cutting and ring harm, which I'm sure is possible.
According to ukranians, yes, for some reason....
Great video Matt. I loved the Deltic part. 👍
Me too. The mercury optimax stroker outboard is a 193 CID 60 deg block and 3 of them would make a nice mini deltic 578 CID 2 stroke OP optimax.
Crazy idea.what about generating energy and positioning a fuel engine piston with electricity at the same time? No crank or rod straight from cumbustion to electric! Electric piston?
The piston is a linear motor that can work as a generator also
You could program different stroke lengths also.
So a Deltic engine to power an electric truck, works for me but I think the load size wouldn't be that great due to space constraints. I'm sure you'd get a couple of pallets on a 17.5T once it's all built and running... 🤣🤣🤣
The Chieftain L60 was an excellent engine in the wrong application, but by fuck it sounded nice.
@thomas Schumacher as I said the engine was used in the wrong application, as a stationary engine running a generator it would have given good reliability, but up and down the revs through the gears constantly were it's downfall.
In hindsight it could have even been used to power a genny and allowed the use of electric transmission on the Chieftain, hopefully not burst into flames like the MAUS... 🤣🤣
Can they rev high these engines
Rev limits are not defined by engine type
Can some kind of valve YPVS being used in opposed piston engine to be more throttlable
Yes.
Opinion on Craig Laycock ?
Who?
@@dirtygarageguy He’s designing a Conjoined Piston Engine, just type his name in YT search bar
Yes I do know him, I was talking to him a couple of months ago about that very thing
Brilliant video thank u ♥️👀👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍
Achates Power have engines in test trucks with dis tech
It's also 100 years old, so?
@@dirtygarageguy The Junkers Jumo 205 had great success in the 30's so absolutely nothing new. But better fuel injection and computer modeling and simulation should help optimise it:) also the Junker Jumo 223 is a funny looking one.
next: ilmor 5 stroke engine, more efficient?
In my opinion all I see is heavy and high recep I can’t ever see this sort of thing making ground breaking power 😁 although I’m interested in this duke engine stuff not much about on them things ? Believe it’s some cosworth buddies behind it. I’m not expert I just like this sort of stuff. My capacity fusion 360 and 3D printer with a self taught tig welding course 😂😂😂
I would port oil through the pistons to keep the rings cool. but also- I would make the pistons of stainless steel- with a concave surface on both- and mirror polish them. this would reflect a huge portion of the heat- and keep it from transferring to the metal as much.
Run amsoil interceptor 2 stroke oil, its what i run in my v8 2 stroke.
Yeah then it would act as a reflective wave guide to keep the electromagnetic energy in the chamber.
Opoc engines are nothing new, they've been used in submarines,trucks, and aircraft( the Junkers jumo 205 diesel) and they displayed superior range,reliability,and less maintenance along with less parts(no cylinder heads,head gaskets, only one rod, piston,crankshaft and bearing designs) to inventory. There are more advantages than disadvantages to their use so.......
Drive MBT oplot-t in service in thailand 49 unit and MBT2000 in service in Pakistan 100 unit engine type 6TD-2 1200 HP turbocharger
The next thing we will see is someone "inventing" the Napier Deltic engine for a fucking boat and claiming its revolutionary...
Yes they work but really why add the complexity and the more complex it is the more there is to fail..
@The Workshop You are better than this! At about 9:00 you butcher the heat comparison issue entirely. As you know Engine designs avoid melting components usually by managing fuel, air flow (density), load, ignition timing and lastly cooling. You also know what we do with the heat is very important, all ICE are heat engines.
Assuming similar power out, inlet temps & lambda (A/F ratio) the hot combustion gases start out the same in OP vs conventional engines. Heat Transfer out of this gas is complex, but lets focus on the big differences the engine architectures bring: surface area, expansion and frequency, time & materials (conductivity).
Let assume same bore and effective swept area. Eliminating the head eliminates about 40-45% of the combustion chamber area per piston. This saves a lot of losses, but doesn’t raise temps unless combustion recipes are changed. If all things were equal it would leave temps near the peak for a bit longer, but things are not equal, the OP has two retreating pistons so a 2x expansion speed for the same trapped gas stroke. So its’ combustion gas cools more quickly by doing work (expansion) while the conventional cools its gas into the head.
Also pistons in heavy duty engines where all this really matters are usually made of steel. Depending on alloying, thermal conductivity can be 20% up to an order of magnitude lower than head material. Again this does not raise gas temps (function of combustion recipe) but leaves more heat to do work pushing the pistons apart.
2-strokes fire twice as often so in simple terms there is twice the time at temperature. Yes this can cause a lack of cooling and subsequent thermal damage. But to be fair we are not asking for twice the power from the OP. So we throttle the intake or slow down the supercharger (compound turbo) as Achates does on their class 8 truck engine, to avoid air pumping losses.
www.ccjdigital.com/regulations/article/15065487/walmart-fleet-testing-the-worlds-cleanest-combustion-engine
This makes the cold air change say half, of course we add only enough fuel (half) to get the appropriate lambda so combustion gas is half as dense but twice as often. Half density reduces heat transfer to pistons by half therefore no additional component temp, no thermal damage.
The heat comparison was a direct comparison if you were paying attention... I do make this very clear. As for more heat doing work, you clearly don't understand the system.
@@dirtygarageguy My attention is often diverted by your lurid yet entertaining delivery. But I did hear you blathering on about higher temps and melting parts. That’s not an Engine architecture issue. It’s a combustion recipe issue, predominately. Clearly the Doxford, Jumo, Deltic, Kommer, F-M, etc engines have burnt millions of gallons of diesel without melting.
@@dirtygarageguy Direct comparison to what? Respond to my technical points if you would please. I don’t want a debate, but am always open to learn.
And those engines aren't as like today's engines...
In the video I'm taking the single cylinder and doubling it up so everything (CR, bore, stroke etc) is the same. I do this to show the difference between each system. Apple to apples if you like. If you did that then pistons would melt with all being equal. Reducing the compression, fuelling etc to compensate takes you further away from the optimal, highlighting that issue.
ruclips.net/video/BPr694nlUKE/видео.html
ruclips.net/video/uiXsPkP9jvw/видео.html
Here an OP Uniflow twostroke, 25 years ago. Crank case pumped. Four pistons, two cylinders.
9200 rpm at about the five minute mark. I still have this engine.
There are some real benefits form this layout, some you seem to have over looked, Mathew.
Yeah a 1700 Rotax OP made from 850 Rotax Etec turbo 2 stroke motors.
Yes OP 2 strokes in snowmobiles would be insane.
cant have your cake and eat it too
To make it more efficient, make it a four stroke with valves
No , no, no .to many cranks, too many pumps, too many bearing journals, too many pumping losses, poor packaging, too much frictional losses, too complicated to assemble on a production line.
Look up 2.7 liter opposed diesel. It is much simpler than any 4 stroke, it has only two shafts, no balancing shafts, no camshafts, nothing
Man you have lost the plot.
Because? You're gonna have to give me more than that...
MATT , you are obviously into the theory of engines but please lets see you make something , i bet you would not have a clue , can't wait to see you on the machines , STICK TO WHAT YOU KNOW
Lol you obviously don't know what I do for a living, also look up my easy engine project...
@@dirtygarageguy easy engine project? You got a youtube playlist or a link for that? I'd like to check that out.