Environmental pollution represents today the greatest danger to which the world has to do faces. Several activities of human are accused. Among the more devastative, the transport sector and in particular that of the car remains more to be feared. For control and to reduce the impact of the pollution of this sector on the environment, it is necessary to control the profile of the flow around the vehicle. The structure of the flow around a motor vehicle is strongly separated and swirling. It presents recirculation’s zones of upstream and downstream from this one. For thus modeling these various swirling structures, we carried out a study on three configurations of vehicle. The purpose of this numerical study is to arise the turbulent character of the flow in the near wake of the Ahmed body. The κ-ε turbulent model has been applied. This simulation is based on the Navier-Stokes equations. The results which we obtain make it possible to see that the size of the zone of wake is a function of the extent of separation, of the slack angle, of the rear window and upstream speed. Comparison of numerical results with the experimental plot available in the literature is satisfactory.

Environmental pollution represents today the greatest danger to which the world has to do faces. Several activities of human are accused. Among the more devastative, the transport sector and in particular that of the car remains more to be feared. For control and to reduce the impact of the pollution of this sector on the environment, it is necessary to control the profile of the flow around the vehicle. The structure of the flow around a motor vehicle is strongly separated and swirling. It presents recirculation’s zones of upstream and downstream from this one. For thus modeling these various swirling structures, we carried out a study on three configurations of vehicle. The purpose of this numerical study is to arise the turbulent character of the flow in the near wake of the Ahmed body. The ?-? turbulent model has been applied. This simulation is based on the Navier-Stokes equations. The results which we obtain make it possible to see that the size of the zone of wake is a function of the extent of separation, of the slack angle, of the rear window and upstream speed. Comparison of numerical results with the experimental plot available in the literature is satisfactory.