A Simple Method of Numerical Analysis of Intake Air Flow in Reciprocating Engines

Abstract

The volumetric efficiency markedly affects the performance of reciprocating internal combustion engines. Intake systems can be tuned to improve charging efficiencies at a particular engine speed. We introduce a simulation technique for air flow in intake systems of reciprocating engines. The method is based on the one-dimensional wave equation. We can use this method to predict the variations in pressure in the intake manifold and the volumetric efficiency simply. Comparisons of experimental and predicted pressure waves and volumetric efficiencies are presented. The results of numerical simulation are very similar to those of measurement. It is confirmed that the method is useful for determining the intake manifold geometry at the initial design stage.