Airflow around an Ahmed body André SEURET Master student – Mechanical Engineering Section (SGM) In order to use numerical simulations on cars, turbulence models have to be validated with experimental data. Since the geometrical form is different for each car model, it was decided to perform validation studies on an Ahmed body, which roughly represents a car and is the subject of many experimental studies. While the rear body slant angle may vary to define several cases of flow separation, this simulation [1] considers only a 35° angle. In addition, the flow is considered steady state and is computed using the Reynolds-averaged Navier-Stokes equations with a 40 m/s incoming flow. Flow streamlines allow highlighting the recirculation zone and the trajectory of the flow. These lines are at every position tangent to the velocity vector. In steady state cases, they represent both the streaklines and trajectories. The streamlines are calculated using the open-source visualisation software ParaView [2]. The Ahmed body is rendered in the same program. Some information concerning the simulation isthen directly integrated into the scene using Adobe Photoshop. [1] Tristan Barjavel & André Seuret, Numerical study of the flow around

the Ahmed body, Numerical Flow Simulation course project (2014). [2] ParaView open-source software, http://www.paraview.org/

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