The research conducted concerns the field of the computational fluid dynamics and considers various turbulence models of the Reynolds-averaged Navier-Stokes equations. The study has been carried out in collaboration with Politecnico di Torino and Stellantis, which uses this kind of model in order to predict how vehicles react to changes of geometry. The aim of this project is to analyze how changes in domain meshing processes and turbulence models, can affect the results of the drag coefficient Cx either on different geometry of the same vehicle and on different vehicles. In particular, deltas between different configuration studied will be shown. In order to conduct the study, two different aerodynamic simulation software has been used: ANSA and StarCCM+ (in collaboration with Siemens in order to develop a better algorithm of mesh and turbulence model).