Induction Ramming a Motored High-Speed Four-Stroke Reciprocating Engine—Influence of Inlet Port Pressure Waves on Volumetric Efficiency

Abstract

This paper describes calculation methods and the results obtained from a computer programme written for studying induction ramming in high-speed reciprocating engines. The calculation uses the method of characteristics for analysing the pressure fluctuations in the intake pipe. The calculated airflow figures are compared with results obtained experimentally from a motored air-cooled four-stroke motorcycle engine. Comparison shows a good correspondence between theoretical and experimental results of both the quantity of air flow and the engine speeds at which airflow peaks and troughs occur. The results also clearly illustrate how flow through the valve is affected by pressure variations at the inlet port.