Abstract

Today different types of spoilers are used on cars that are not heavy at the rear to serve as aerodynamic aids to improve their performance. The trunk spoiler functions as a barrier to the airflow passing, so that more pressure is built up above the rear trunk surface. This pressure resulted in inducing a force acting vertically downwards to decrease the car lift force. For this reason, this study is focused on the investigation of aerodynamic performance of lip spoiler on rear trunk of a passenger car. All of the analyses and modifications in this study were carried out using the computational fluid dynamics (CFD) software “ANSYS Fluent 15.0” and the CAD modelling in “AutoCAD 2015”. The results of the simulation showed that adding the lip spoiler on the trunk resulted in a significant decrease in lift coefficient of the car by 95.0%. However, the drag coefficient of the car was increased by 2.25%. The results of the study were found to be in agreement with the effect of spoiler reported in the literature. Therefore, adding a lip spoiler on the rear trunk of a passenger car will improve the stability and performance of the car.