Simulation of Passenger Car Aerodynamics in Overtaking Manoeuvres with an Adaptive Lattice Boltzmann Method

Using the freely available DriAer passenger car geometries, the benefits of our Cartesian adaptive lattice Boltzmann solver AMROC-LBM for simulating the aerodynamics of vehicles in motion are demonstrated.A large eddy simulation (LES) approach with wall function model is applied to approximate the transient turbulent flow field, while motion is incorporated in a scalable way by representing complex moving bodies with signed distance level set functions and moving wall boundary conditions.The adaptive lattice Boltzmann-LES method in AMROC-LBM is first validated against experimentally measured drag coefficients of a single car geometry.Subsequently, a study of an overtaking manoeuvrer at 25% scale is conducted and verified with previously obtained simulation results from StarCCM+.Finally, predictions for a realistic overtaking manoeuvrer at full scale are presented.