Method for internal combustion engine control using pressure ratios

摘要

The invention comprises a method to operate a direct-injection engine operative at various air/fuel ratios. The method comprises monitoring in-cylinder pressure, along with a corresponding engine crank position to periodically to determine instantaneous in-cylinder pressure states corresponding to the engine crank position during compression and expansion. Pressure ratios are determined based upon the instantaneous in-cylinder pressure states. A combustion heat release is determined based upon the pressure ratios. An aspect of the invention comprises extending the operation to diesel, diesel premixed and to HCCI engines.