Numerical Investigation on Motorsport Overtake Manoeuvre in Crosswind Conditions

Existing technical literature has primarily focused on the upstream wake effects of single-seater race cars during overtaking, often neglecting the critical factor: crosswinds. This study presents a quantitative computational fluid dynamics (CFD) analysis of how crosswinds impact the aerodynamic loads of interacting race car models during an overtake manoeuvre. For numerical validation purposes, a wind tunnel experimental campaign was carried out on a 35%-scale hill climb race car model to evaluate aerodynamic forces and wake pressure mappings at different ride heights. RANS-based simulations were performed to assess the impact of crosswinds (β = 2°, 6°, 10°) on an isolated race car. Subsequently, a quasi-static approach was used to quantify the effect of crosswind (β = 10°) on an overtaking car under different path strategies. The findings indicated that the overtaking car's performance remained largely stable when a driver opts for overtake paths against the crosswind direction (i.e., 'clean freestream' side). However, when the overtaking paths are favourable to the crosswind (i.e., 'dirty freestream' side), the overtaking car's performance is significantly affected by wake interference throughout the entire overtaking trajectory.