Abstract
Road vehicles such as SUVs or pickup trucks are described as bluff bodies. When the air flow passes over the road vehicles the flow will separate at the rear of the vehicle, forming a large low pressure turbulent wake region behind the vehicle. The formed pressure drag posts resistance on the road vehicles and thus increases the work done by the engine to propel the vehicle. The purpose of this paper is to present the development and design of drag reducing devices for SUVs by studying the SUV’s aerodynamics. Numerical simulations using commercial software package — FLUENT were performed in order to study the aerodynamics behind the vehicles. A computer model of the Ahmed Vehicle Model was selected as a benchmark test. This Ahmed Model is a simple geometric body that retains major flow features where most part of the drag is concentrated. Seven different spoiler designs for the SUV have been studied. Their results for the SUV’s aerodynamics have been presented through velocity vectors, pressure contours, and aerodynamic lift and drag plots. One spoiler design was found to be able to reduce aerodynamic drag and others were found to be able to reduce the lift.