Numerical Analysis of the Piston Crown Geometry Influence on the Tumble and Squish in a Single Cylinder Engine

The objective of this paper is to simulate the air flow (cold run) inside a single cylinder research engine for different geometries of the piston crown and investigate the influence of them on the Tumble coefficient and Squish. The study was conducted through the software star-CD, with the module es-ice (Expert System - Internal Combustion Engine) and simulations of the air flow with the flat piston were carried out at the first time.

Once the simulation methodology was created according to its correlation with the experimental results, the geometry of the piston crown is changed and other numerical simulations are performed. Thereby, with the comparison between the obtained results for different geometries, the air flow inside the combustion chamber can be characterized, and the effects of the geometry changing on the Tumble coefficient, Squish and other flow parameters verified.