Patent ID: 7865291

Claim:
A method of calculating a volumetric efficiency (VE) for an internal combustion engine having a predetermined air induction configuration, comprising the steps of: providing a controller in electrical communication with the engine and configured to calculate said VE; providing an engine exhaust manifold pressure P ExhMnfd to the controller; calculating a modified engine exhaust manifold pressure with the controller, said modified exhaust manifold pressure being said exhaust manifold pressure P ExhMnfd raised to an exponential power, said exponential power having a value that is associated with the predetermined air induction configuration; providing an engine intake manifold pressure P IntMnfd to the controller; calculating an engine pressure ratio with the controller, said engine pressure ratio being the modified exhaust manifold pressure divided by the intake manifold pressure P IntMnfd ; and calculating said VE using the calculated engine pressure ratio with the controller, wherein the volumetric efficiency is used to control operating performance of the internal combustion engine.