The Unsteady Gas Flow Behaviour in a Charge Cooled Rotary Piston Engine

Mathematical models of the open cycle gas exchange process and the closed cycle combustion process are developed for a Wankel engine. The theoretical model of the complete engine operating cycle is programmed for a digital computer and the results are shown for a small single rotor charge cooled Wankel engine. The predicted pressure diagrams in the working chamber and in the inlet, transfer and exhaust ducts are compared with measured values as is the predicted volumetric efficiency relationship with engine speed. The predicted charging efficiency relationship with engine speed is also compared with the measured brake mean effective pressure characteristic to demonstrate the usefulness of the theoretical model.