3D numerical investigation of the air flow in the wake of a compact SUV-type vehicle fitted with optimized horizontal Savonius turbines

This paper presents a numerical study of the airflow characteristics in the wake of a compact SUV vehicle on which two models of Savonius optimized wind turbines (Bach optimized and conventional with a ratio overlap of 0.2) are mounted in the “bull bars.” The turbines consist of two blades placed horizontally at the end of which are two generators capable of converting wind energy into electrical energy necessary for the operation of vehicle accessories. The Fluent solver was used to perform the steady-state incompressible 3D numerical simulations of the RANS equations, and the realizable k–ε turbulence model with the Menter–Lechner wall functions was used to solve the problem mathematically. The numerical results obtained show, respectively, 0.403 of the drag coefficient for the vehicle alone and 0.404 of the drag coefficient for the vehicle equipped with “bull bars.” By integrating the wind turbines in the “bull bars” located at the front of the vehicle, we were able to obtain 0.404 as the maximum values of the drag coefficient for the optimized Bach wind turbine when the angle of attack of the blade was 120° and 0.408 for the conventional turbine with 80° as the angle of attack. The position and optimized profile of the turbines had no impact on the aerodynamic characteristics of the base vehicle and only contributed 0% for the first model and 0.99% increase in drag for the second model. The optimized Bach model is therefore the most favorable.