2007-03-09 03:25:48 · 3 answers · asked by goring 6 in Science & Mathematics ➔ Engineering
Ideal Gasoline Engines (Maximum Efficiency) use the Otto cycle. The efficiency of the Otto cycle under the cold air standard assumptions (constant specific heat of air with varying temperature) is 1 - 1/(r^0.4) where r is the compression ratio. (0.4 comes from 1 - Cp/Cv)
Typical compression ratios of gasoline engines vary from 6 to 12. So the efficiency would be between 51% and 63%
2007-03-09 09:33:35 · answer #1 · answered by HaSo 3 · 0⤊ 1⤋
If we consider one Carnot Cycle between the adiabatic combustion temperature of gasoline (2,300 K) and the admitted working temperature for steel (925 K), the expected efficiency would be 59%. The largest efficiency already attained, in maritime Diesel engine with 90,000 HP is 52%. In Otto Cycle engines, which use C gasoline (with anhydrous alcohol), it reaches 32% and those which use hydrated alcohol reach 38%.
2007-03-09 11:49:54 · answer #2 · answered by CM 2 · 2⤊ 0⤋
actually gasoline engines has no efficiency, so its rubbish dont use it efficiency= %0
2007-03-09 20:03:00 · answer #3 · answered by arash 1 · 0⤊ 0⤋