Abstract
A new nonlinear discrete model of a spark ignited gasoline engine is designed. With good accuracy in a large field, it predicts the engine dynamical behaviour in terms of intake manifold pressure, fuel-air ratio, torque, speed and pollutants concentrations in the exhaust gas as response of throttle opening, spark advance and injectiontime strategies. A new approach to study fuel economy and pollutants emission minimization is worked out. (A)