Maximum thermal efficiency of an Otto cycle

Description

The constant volume adiabatic flame temperature is the temperature that results from a complete combustion process that occurs without any work, heat transfer or changes in kinetic or potential energy. In the constant volume adiabatic flame temperature case, the volume of the system is held constant hence there is no work occurring. An Otto cycle of a gasoline engine, is an idealized thermodynamic cycle which describes the functioning of a typical spark ignition reciprocating piston engine.The Otto cycle consists of isentropic compression, heat addition at constant volume, isentropic expansion, and rejection of heat at constant volume. For the constant volume adiabatic process, combustion is thought to occur instantaneously when the piston reaches the top of its apex. The thermal efficiency of an Otto cycle is dependent on the compression ratio and the ratio of specific heats.

Related formulas

Variables

nottoThe thermal efficiency (dimensionless)
CRThe compression ratio (dimensionless)
γThe ratio of specific heats Cp/Cv (dimensionless)