Engine intake airbox CFD optimisation and experimental validation tests

Abstract

The effective power of an internal combustion engine is determined by the amount of air that is drawn into the cylinder. One of the basic requirements for the intake is the even filling of all cylinders. This paper deals with the design of an airbox 4- cylinder 2.2 liter naturally aspirated SI engine. The CFD simulation of the air flow through the serial airbox was performed. This showed an uneven filling of the cylinders. With the help of CFD simulations, the shape of the airbox was optimized to improve the uniformity of the cylinders filling. The validation tests of the real airboxes on the flow bench were performed. The standard airbox and the airbox with the optimized shape were compared. The results confirmed the CFD simulations outputs. Furthermore, it has been shown that the air filter chamber can contribute to the uniform filling of the cylinders. The research resulted in the optimization of the engine's intake tract airbox shape.