Numerical study on aerodynamic drag reduction and energy harvest for electric vehicle: a concept to extend driving range

Abstract

Energy efficiency of road vehicles is highly attributed to its aerodynamic performance. Over the last decades, significant reduction of aerodynamic drag has been made. But, beyond the current achievement, further improvement become a challenge for car industries and professionals working in the area. This paper focuses on new approach to further find aerodynamic performance improvement particularly for electric vehicles. Therefore, a preliminary numerical study on ducting and concept of energy harvesting from aerodynamic resistance is introduced as an alternative to improve energy efficiency. Ducted and slightly modified Ahmed model is used to study aerodynamic characteristics of ducted models and how ducting would contribute to the reduction of energy consumption due to air resistance. Three-dimensional, incompressible, and steady flow governing equations are solved by CFD code (PHOENICS ver.2018) with extended turbulent model proposed by Chen-Kim (1987). From the study, it is found that the total drag reduction of over 15% on the ducted models compared to the base model. The kinetic energy preserved due to ducting is also significant. Harvesting this energy and utilizing it to extend driving range is believed to be a potential area to be dealt in detail. Therefore, the idea of duct application and energy harvesting introduced in this paper, either to reduce or use aerodynamic resistance is expected to have potential contribution to the development of future energy efficient road vehicles.