I'm not sure I follow you. Do you mean use the heat in the cooling jacket to boil water to make steam to run one rotor while the other runs internal combustion?

If so, my thoughts are just that I don't see that reducing the peak temperatures or reducing the temperature variation across the engine. What I was suggesting, by alternating, was to capture and use the waste heat immediately and allowing the combustion chamber to be free of hot spots, allowing higher pressure levels without detonation during the internal combustion cycles.

Technically, what I am suggesting is not, in fact, a 6 cycle engine. It's actually an alternating mode co-generating engine. Normally, co-generation is implemented by using the waste heat to fire an external boiler that feeds an external steam engine, so it's normally only implemented in situations where fuel consumption rates are so large and the engine bay space is large enough to allow it, such as in large maritime installations or in stationary power-plants. Using the alternating mode, cogeneration could be incorporated into the wankel at only a fairly modest space penalty.

Unfortunately, I don't see any way that our existing PCM could do the job, even with a piggyback controller, so building a working prototype would be a pain, and beyond my skills or assets (I don't have the workspace or cash flow to sink into such an R&D project).

Distilled water takes a considerable amount of energy to produce.

Edit: oops, pwned by thread resurrection!

Distilled water takes a considerable amount of energy to produce.


....and also about the same price as gasoline.

So lets say you forget to fill up your water tank, will it survive an overheating?

If the water isn't recovered and recycled, then that would be a definite no. On the other hand, I do recall reading about a system that DARPA was developing to allow potable water to be extracted from vehicle exhaust to provide soldiers with a secondary source of drinking water. I don't know how far along that research has gotten; but if it's mature at this point, then I would suggest using that equipment or a variant of it to capture water vapour from the combustion phase and steam from the steam phase so that the even if the gear isn't much better than 50% efficient, it would still reclaim enough water to keep the engine running as long as there was fuel.

It might be best to have two water sources. One would be a tank of distilled water with an anti-freeze additive (perhaps a simple alcohol like ethanol) and the rest would come from recycling. Alternately, a bottle of the anti-freeze might be separately metered into the water supply to keep the freezing resistance constant (I'm assuming that the recycling system wouldn't reclaim the antifreeze as the catalytic convertor might oxidise the anti-freeze into CO2 and H2O).

I assume someone already said this, but it's not 6 cylinders, it is only one. Also it is 6 strokes or cycles 7 events. It would not work in our engines as we operate much like a 2 stroke and do not have the ability to "add" extra strokes.