High precision numerical simulation of passenger cars based on numerical wind tunnel.

This study investigates the high-precision numerical simulation technology of passenger cars based on a numerical wind tunnel, develops a virtual numerical wind tunnel model based on the existing vehicle wind tunnel in China, and simulates the flow field characteristics in the actual wind tunnel by choosing the appropriate mesh strategy and boundary conditions. The realizable k-ɛ, shear stress transport (SST) k-ω, and SST detached eddy simulation turbulence models are used to simulate numerically the aerodynamic drag and lift of the real vehicle. These simulated values are compared with the actual wind tunnel test values. Results show that the numerical wind tunnel can successfully simulate the flow field characteristics in the wind tunnel, such as turbulence degree, airflow deflection angle, pressure gradient, and boundary layer displacement thickness. Moreover, the simulation accuracy of the numerical wind tunnel is higher than that of the traditional rectangular open-domain simulation. This study confirms the capability of the numerical wind tunnel in simulating the flow field characteristics in wind tunnels, thereby improving the numerical simulation accuracy and providing a new perspective for the numerical simulation study of automotive aerodynamics.