Wankels are interesting engines, really. They use a 3-sided rotor that spins and kinda slams into the side to compress or exhaust gasses. The main problem with Wankels in sealing loss. They need seals to keep the cycles sealed in their specific chamber. The problem is that the seal must go from the extreme temperature of combustion straight to the cold temperature of intake and in the process they expand and contract, resulting in some seal loss.
We have scavenged piston engines, why not wankels? I propose a wankel engine that has rotary valves, much like the Coates Patented Rotary Valves (link). There would be two of them in each spot and they would be in the 2 places where the rotor is at its greatest expansion. This is because with the scavenged design, the place of combustion would change each time. Since by scavenging the exhaust and intaking all at once, this frees up an extra cycle. This means it can start the process over again that much sooner. This means there would also be sparkplugs in the two areas where there is the greatest compression.
So the wankel gets its intake and exhaust all in one, making it more efficient as both cycles individually are inefficient. It also makes more power since it would have twice the combustion strokes per every rpm. It also prevents seal loss due to temperature change because the fact that the intake and exhaust happen all at once and the fact that it varys each time mean that there is essentially no great temperature difference from cycle to cycle. And the rotary valves allow for variable valve timing so more control on low rpm and high rpm performance.-- acurafan07, Nov 16 2007 Coates Rotary Valves http://www.coatesengine.com/Pretty cool [acurafan07, Nov 16 2007] Illustration http://i210.photobu...l_Cycle_anim_en.jpg [acurafan07, Nov 20 2007] Sorry to be way off tangent here, but does a wankel lubricate itself? If so, then perhaps a grease wankel would be cool. I'm tired, gn.-- quantum_flux, Nov 16 2007 This idea doesn't seem very good to me right now, but I'm tired too...-- BJS, Nov 16 2007 I don't think it would work the way you describe it. You would first need to change the shape of the path the rotor takes, and then change the motor design itself.
But, scavenging a wankle, [+]
I don't understand your drawing, are you still using the original intake/exaust ports? If not, how is the air exiting the block, I only see it entering. You need an in and an out for scavenging-- evilpenguin, Nov 20 2007 Actually, in both places where you see a rotary valve, there are actually two side by side (one for each purpose). You just cannot see it since the drawing isn't 3D. These are the only open ports in the entire engine, and I think it would be pretty easy to implement on the current design of a wankel.
Thanks for the bun.-- acurafan07, Nov 20 2007 random, halfbakery