What compression ratio is best for a fusion reaction with hydrogen and oxygen?

Answer 1

If you are talking about ignition ratios of the gases themselves... 2:1

On a mole per mole basis, or on a molecule per molecule basis (using whole numbers), hydrogen gas reacts with oxygen gas:

H2 + 1/2 O2 --> H2O or, using whole numbers,
2 H2 + O2 -->2 H2O

If you were to take, at equal temperature and pressue, a 2 litre balloon of hydrogen gas and a 1 litre balloon of oxygen gas and mix them together well, you'd get a 3 litre balloon that was filled with a very explosive gas that would "burn" perfectly if ignited with a spark or flame. Unfortunately, a balloon of this size would likely deafen you, and might blow out the windows of the room that you are in.

Answer 2

I THINK you are asking what is the ideal compression ratio for a piston engine that burns hydrogen as a fuel. My guess is that because hydrogen burns more rapidly than gasoline or diesel, the compression ratio needs to be on the low side, like maybe 1:8? And please drop the term "fusion", because then we're talking about tens or hundreds of millions degrees temperature, and in fact, fusion would occur at just about any "pressure", only that at low pressures the fusion rate would be slower.