Detached Eddy simulation of the cornering aerodynamics of the Ahmed reference model

Modern vehicles are capable of travelling through tight corners at speeds where aerodynamic forces become significant. An investigation has been conducted to determine the effect of the cornering condition on the aerodynamics of a simple bluff-body. A comparison study of the Ahmed reference model [1] travelling in a straight line and through a constant radius corner has been conducted. A commercial solver ANSYS Fluent 14.5 was utilised to perform Detached-Eddy simulations (DES) of both conditions. Simulations were validated against straight-line experimental data. The flow conditions through a corner were found to result in significant changes to the structure of the time-averaged near wake. The dominant longitudinal vortices were affected in size, strength and trajectory when compared to the straight line case. An increase in the drag coefficient was found to result for the body when cornering. Results demonstrate the inappropriateness of aerodynamic development purely in the straight line condition for vehicles regularly travelling in the cornering condition.