Review on Vehicle's Aerodynamic Drag Reduction

Recent spikes in fuel prices and concern regarding greenhouse gas emissions, automotive design engineers are faced with the immediate task of introducing more efficient aerodynamic designs vehicles. The aerodynamic drags of a road vehicle is responsible for a large part of the vehicle’s fuel consumption and contribute up to 50% of the total vehicle fuel consumption at highway speeds. This review intends to provide information on the current approaches and their efficiency in reducing pressure drag of ground vehicles. The review mainly focuses on the methods employed to prevent or delay air flow separation on the body of vehicle. The exterior styling and aerodynamically efficient design for reduction of engine load which reflects in the reduction of fuel consumption are the two essential factors for a successful operation in the competitive world. The main objective of the study is to predict the drag coefficient experimentally as well as computationally. Several factors that influence the drag coefficient such as flow separation, vortex and the effect of pressure coefficient have been studied. Passive control methods such as Vortex Generator (VG), Spoiler, Surface dimples and Diffuser are among the methods that have been reviewed.