A CFD solver based on a Lattice Boltzmann approach and optimized for GPU execution is utilized to study the aerodynamics of an existing passenger car.Several model variant of Chinese automotive OEM Changan have been investigated.The CFD results of a baseline design and various design changes are compared to data collected during wind tunnel experiments.This paper provides a brief overview of the underlying numerical approach,followed by modeling requirements and ends with a detailed discussion of the CFD results.In addition,the impact of the current workflow using GPUs and an interactive setup scheme is evaluated.