抄録
A method of one dimensional analyses on unsteady gas flow in exhaust and scavenging manifold is developed, in which specific heat ratio is a function of gas temperature and gas mixture. The two-step Lax-Wendroff' s method is used at inner points in pipe and the characteristic method of semi-ideal gas is applied to boundary condition of pipe.
The simulation by this method conserves energy flow integrated over one engine cycle better than conventional simulation assuming that specific heat ratio is constant, while there is practically no difference between the predicted pressure waves in pipes by two methods.
