Trajectory and impact dynamics of snowflakes: Fundamentals and applications

This review paper examines the dynamics of snow accumulation on vehicle surfaces and its impacts on vehicle performance and safety. It focuses on the use of computational fluid dynamics (CFD) to model snow ingress in vehicle air intakes and its interactions with sensors in advanced driver assistance systems (ADAS). Central to these studies is the coefficient of restitution ( COR ), which measures the elastic properties of snow upon collision with vehicle surfaces. The paper provides an overview of various turbulence models, such as large eddy simulation (LES) and Reynolds-averaged Navier-Stokes (RANS), assessing their effectiveness in simulating the aerodynamic fields that affect snow trajectories. It critically reviews existing models and highlights recent experimental studies related to COR of snowflakes based on different impact velocities and particle conditions. The discussion on the practical implementation of these findings in automotive design underscores their importance in enhancing vehicle safety and reliability under extreme weather conditions.