by johnh » Fri Aug 26, 2005 6:39 am
Don't know on this one.
Every now and again one sees reports of very low volumes of H running engines but very little solid proof.
The 4% to 78% limits on hydrogen flamability in air are based on weight/weight ratios not volume so you need to be a little careful because h2 is so light.
Theoretically if we take the stoichiometric AIR/hydrogen ratio ( thats air volume not oxygen volume) which should be the point of maximum power output for an engine it works out that the Hydrogen needs to occupy ~29% of cylinder volume at atmospheric pressure. and means that the engine power is reduced by about 15% compared to Petrol because not enough H2 or oxygen can be crammed in.
If we use hydrogen direct injection to put the H2 in after the cylinder is full of air the theoretical power output is 15 to 20% better than Petrol;
This information comes mainly from "Hydrogen use in a postal vehicle" by R Billings. you will have to get this off the net archives for about 1995 cause it does not seem to be on the net now.
We have claims that Ortho H is better or mon-atomic H is better but no real live roadtest figures like Roger provides, and it gets confusing when people without test equipment claim mon-atomic hydrogen production when conventional science (AND A HYDROGEN WELDING TORCH ) prove that hydrogen only exists in in di-atomic state below about 800degrees C.
I don't think we can work this one out on paper - its going to be a case of try it in your vehicle and see. AND please post some real live figures!!!
Regards
JohnH