Hello,
I would like to design a new type of gasoline combustion engine, a free piston engine.
Unlike in a conventional engine, the piston is not constrained to a crankshaft in a free piston engine, but moves freely, its movement being converted to electricity by an actuator.
Now, would it be possible to built a gasoline engine like this with real high compression ? Say 25. In a normal engine, this would cause a lot of knocking, making it impossible to built. In a free piston engine, however, its possible to have a very high piston acceleration after top dead point, and the goal would then be to engineer the acceleration such that the burn becomes a constant pressure burn, avoiding the knocking at 25 compression.
Does anybody have information on this ?. What kind of piston acceleration is needed, and what kind of control on this is necessary to make such an arrangement workable ?
Best Regards, Henri.
If someone share any idea, he/she becomes a co-owner of your intellectual property. Any public disclosure of ideas would not allow to file a patent.
This is not about patents. This site is public, whatever I put on this site is public, and not patentable.
That's what I said "whatever I put on this site is public, and not patentable." But any answer on your question is potentially patentable.
Ok, got you ! . Thanks. You seem to suggest that anybody reading my question, could take that as inspiration, and patent the answer, not publishing it.
In order to try to avoid this, I will give myself an (unpatented) anwer, which is from now on in the public domain:
I will assume a spark ignited engine with a compression ratio of 25 is possible, provided the movement of the piston and the gas expansion is fast enough so that the peak pressure stays below 15 Mpascal. The hot gas burn is assumed to take 1 millisecond.
It is also necessary to have direct control on the expansion of the gas, because the burn time may dynamically vary with about 20 %, due to random variations, temperature and pressure variations, and gasoline composition variations.
All numbers in this answer may be off up to a factor 5. So, if any of this can be realized in the fashion as explained above, taking the given numbers only as guidelines, assuming the actual numbers may be up to a factor 5 off, this will be assumed to be in the public domain from now on.
Only, it would be helpful if somebody could give me some hint on the actual values.
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