Numerical Simulation and Analysis of Aerodynamic Characteristics of Road Vehicles in Platoon

Abstract

—With the spiking of fuel price and increasingly stringent emission regulation requirements, it brings a more daunting challenge for researchers and engineers to reduce the aerodynamic drag of road vehicles. When a vehicle is traveling in a platoon, the wake flow of the leading vehicle can affect the aerodynamic characteristics of the following vehicle. Due to the interaction of the flow field of the involved vehicles, the aerodynamic drag of each vehicle changes, which results in the alteration of the vehicle's fuel consumption. In the study, a single MIRA model was generated using CATIA software. The external flow field of the MIRA was imitated by CFD simulation. The numerical result of the drag coefficient was compared with the wind tunnel test results of Hunan University, China. The drag coefficient errors between the simulated value and the experimental result are less than 6%. It implies that the simulation and tests achieve a good agreement. The benchmark indicates that the numerical simulation method is reliable. By means of CFD simulation, we explored the effects of separation distance, the number of vehicles in the platoon, the shape of the vehicle, and the speed of vehicle platoon on the aerodynamic properties of vehicles in platooning. The results of the numerical simulation demonstrate that although the influences of the aforementioned parameters on the aerodynamic properties of leading and trailing vehicles in the platoon are different, but the average drag coefficient of vehicle platoon is lower than that of a single vehicle, which is beneficial to improve the fuel economy of vehicle.