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I designed an engine for a college project that is single stroke that is 2 stroke. It could be 4 stroke but we kept it simple for the project.
We were able to double displacement without increase engine size.
The Shop
Don't seeing this making good power.
1 because there are a lot of moving parts and no additional combustion force.
2. The combustion doesn't have anything solid to push against because of the cylinders pushing apart. doesnt seem like it would have tourqe.
I like the opposing pistons. The cylinder head on a typical engine is a huge heatsink, lowering thermal efficiency and increasing emissions. In addition, within reasonable compression ratios, the lack of valves/valve pockets means the pistons can be formed to provide a very tidy combustion chamber which is critical for high thermal efficiency. The ability to tailor the tumble and swirl of the incoming charge makes a huge difference in emissions and part throttle response. Good stuff.
Direct injection, good.
The lack of a valvetrain and all the parts is good. Again, depending on VE, overall friction and rod loads the engine should be able to rev pretty high. The extra crank adds relatively little to the overall friction (pistons/rings and valvetrain are the big hitters) but it does add quite a bit of inertial loading which hurts acceleration.
On the other hand, I see some of the same constraints that current two strokes must deal with. Without a dedicated stroke to expel exhaust gasses and fill the cylinder it's difficult to see how this design could make power (torque) over a wide range. The supercharger will definitely help on the intake side but there's just so little time at high rpms to completely evacuate the cylinder of spent gases, even though it seems this design has exhaust ports 360 degrees around the cylinder they are open for a relatively short time.
I don't see this coming to moto but I'll bet Mitch Payton would love to port and make pipes for those babies!
Also, what is going to suck the oil out of the top. I dont think it will work the same as a conventional 4 stroke in the way of top end oil flow
2.) They are pushing against each other in the engine. It doesnt have to be solid non moving object. It just has to have an opposite reaction. It will still make torque. There is a cog joining the 2 crank shafts stop them from moving independently if that answers your question.
You should know the answers to both of those if you truly understand relative motion
Regarding the Double Stroke, I'm sure the exhaust ports (top of the cylinder) open quite a bit before the intakes (bottom on the cylinder). Therefore, the high pressure in the cylinder will naturally blowdown as the exhaust port is exposed by the piston. The rapid mass acceleration of all the exhaust gas towards the exhaust port tends to leave a low pressure area in its wake. This, along with the pressure generated by the supercharger creates a nice pressure differential for the intake charge to move into the cylinder, again, helping to scavenge and dispose of the remaining residual exhaust before the exhaust port closes.
Regarding the oil flow, all radial airplane engines have cylinders "upsidedown". They somehow manage to make them very reliable.
I wonder if this would work with diesel applications where no spark is needed. Basically has a built in dual fueler. But where diesels have much more compression I don’t know if it would be super efficient since there is nothing super stable to push against.
I wonder if this would work with diesel applications where no spark is needed. Basically has a built in dual fueler. But where diesels have much more compression I don’t know if it would be super efficient since there is nothing super stable to push against.
Pit Row
https://www.youtube.com/watch?v=adoST4TbJz4
I didn't notice how the exhaust was getting out. It looked like it flowed somehow through the center of the engine. Possibly with a turbo having a forced induction you can really pump as much air in as you want because of the direct injection, any extra air into the cylinder would just go out the exhaust and it would just be air, no fuel mixed with it yet. I don't know what affect that would have on emissions though.
https://en.wikipedia.org/wiki/Commer_TS3
I worked on the 5 stroke motor in this video from 3.14
https://www.youtube.com/watch?v=pRnQFGskg9w
The motor can lay sideways, too...making it an "opposed boxer" which would REALLY help with several design and engineering factors...from center of gravity to aerodynamics (lower hood and over-all dim's of the engine compartment, etc.) both of which have been factors when using a boxer engine as seen in new designs like Toyota's "86".
A short stroke version of this would take very little room and have minimal rotating mass. A longer stroke version would take more room and have more mass; but, typical design std's imply that it would make more torque.
Your cranks are out-board and opposing. This is an interesting design point when it comes to harmonics and balance. Those cranks are an engineers dream when it comes to utilizing opposing forces.
I like it.
No typical valve-train. Soooooo many fewer PARTS. Sooooooo easy to build. This design has the opportunity to utilize modern materials and can truly benefit from being a "clean sheet" design.
Nice!
https://youtu.be/Tx3wDTzqDTs?start=53
In terms of forces / torque, currently the head bolts take a heap of force without making use of that load. So the second piston is trying to capture that energy.
Not sure about the life of the chain / drive connection between the two cranks. That systen will be working hard.
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