Simulation of a standard emissions test cycle in a bench dynamometer

This work describes a mathematical model developed for a data acquisition and control system able to reproduce the FTP-75 emissions test cycle in a bench test dynamometer. The model correlates the vehicle speed with the engine speed. Aerodynamic and rolling resistance forces arc calculated from vehicle weight and tire pressure data. The model was tested against data available from two different vehicle models that use the same engine type. The emissions test standard cycle generated by the model based on the engine speed is presented, as well as the general characteristics of the actuating forces. Results from simulation prove the model to adequately correlate engine speed and the resistance forces to vehicle movement at a given speed.