Abstract
A volumetric efficiency of reciprocating engines can be improved by fluid dynamic effects in a suction pipe line. This paper .presents a calculating method of the volumetric efficiency in suction process considering pulsation effects. A state equation of cylinder gas in a four cycle engine is expressed in terms of the acoustic impedance at cylinder port of a piping, and it is solved in frequency domain. Its result is converted to time wave, and the charged volume is obtained as the value at the end of suction process. Some calculations are carried out for simple models and for a practical model to demonstrates its usefulness and to find the tendency of pulsation effects.
