Crosswind effects on aerodynamic interactions and wake dynamics in vehicle platoons

Abstract

With the advancement of intelligent transportation technologies, safety requirements for platoon driving have become increasingly prominent, and crosswind conditions can significantly affect the stability of platoon vehicles. However, current research on the lateral stability of platoon vehicles remains limited. This study combines numerical simulations and wind tunnel experiments. Nine working conditions are constructed by setting three inter-vehicle distances and three lateral displacements for the platoon vehicles, aiming to investigate the factors affecting aerodynamic characteristics under crosswind conditions. The results indicate that the left-rear vehicle is affected by 8 m/s crosswinds, with its flow field tending toward that of a single vehicle. The directly-rear vehicle is susceptible to interference from the combined wake and the crosswind flow at shorter inter-vehicle distances, and requires a moderate spacing to maintain stability. The right-rear vehicle benefits from the wake of the front vehicle at shorter distances, but as inter-vehicle distance increases, the stability of the flow field diminishes. Furthermore, when the distance is small, trailing vehicles are strongly influenced by the combined effect of the front vehicle’s wake and crosswind, resulting in complex aerodynamic behavior; when the distance is large, trailing vehicles are largely detached from the wake influence, and the flow field approaches that of a single vehicle. These findings provide theoretical guidance for optimizing platoon driving safety under crosswind conditions and offer a basis for the design of related operational parameters.