Numerical investigation and optimization of aerodynamic performance of an SUV model motor vehicle

With the continuous displacement of air around moving motor vehicles, aerodynamic resistance forces are formed, which have a significant impact on the vehicle's design, performance and fuel economy. As the speed of the vehicle increases, the impact of the aerodynamic forces also increases. For this reason, optimizing the exterior designs of passenger-type motor vehicles, especially automobiles, is of great importance in terms of performance, safety and fuel economy. In this study, the aerodynamic performance of a passenger type motor vehicle model in the category of J segment and Premium SUV was numerically investigated using ANSYS Fluent software. A 1:1 scale and one-dimensional model of the vehicle was drawn in SolidWorks, with reference to the original dimensions of the vehicle. The effects of rounding sharp lines on the vehicle model, reducing the windshield angle and roofline slope on the drag (CD) and lift (CL) coefficients were investigated. As a result of the changes made according to the analysis results, the CD coefficient of the model, which was 0.255, was reduced by 20% (0.204). However, the CL coefficient, which was -0.218, was reduced to -0.337. The maximum pressure value of 559.2 Pa acting on the vehicle surface was reduced by 4.05% to 536.5 Pa. As a result of the geometric revisions, a more stable profile was obtained in the streamlines and the areas where the speed vectors lost speed on the vehicle surface were reduced. Thus, the aerodynamic efficiency of the model is increased.