Volume of hydrogen needed to power engine

[CharlZA]

Hi, a friend of mine that's studying chemical engineering and I are looking at the viability of building a hydrogen powered car. We're doing our research and calculations at the moment. We've looked at some past research and he's decided on a air/hydrogen ratio of 137.33/4 because we need to keep it quite lean. I'm just trying to figure out how many moles of Hydrogen we'll need to supply to the engine per liter of engine capacity or at least how to convert the amount of gasoline that the engine uses at full throttle to the amount of moles of hydrogen we'd need to supply it with.

Thanks

 

[MJCronin]

This might be helpful....

http://www1.eere.energy.gov/hydrogenandfuelcells/tech_validation/pdfs/fcm03r0.pdf

MJCronin
Sr. Process Engineer

 

[TD2K]

Pick a car. Say it gets 30 miles/gallon. You know how many gallons of gasoline it uses. Gasoline is about 20,000 BTU/lb so you have an estimate of the total energy being released in the cylinder. H2 has a heating value of about 61,000 BTU/lb.

Energy efficiency of the two engines isn't something I know much about. I would suspect they are similar but I'm not certain. Honda has some H2 powered Civics, mostly in California. I would start by looking at their specs for mileage (in whatever units they use) and compare those to conventional gasoline powered Civics as a check to the above method.

http://www.engineeringtoolbox.com/fuels-higher-calorific-values-d_169.html