Saturday, September 26, 2015

Passenger Car Aerodynamics

When we think of computing the external aerodynamics on a passenger car, we often assume a super-computer and months of grid generation are necessary for the task. However, Stallion 3D with HIST (Hanley Innovations Surface Treatment) can accomplish the task on your ordinary Windows Laptop or PC running 7, 8 or 10.

DrivAer model solution using Stallion 3D - RANS solver.

No Simplifications

Stallion 3D makes no simplification in the physics of the problem. Instead, it utilizes the computation power that is hidden in your personal computer (64 bit & multi-cores technologies). The software simultaneously solves seven unsteady nonlinear partial differential equations on your PC. Five of these equations (the Reynolds Averaged Navier-Stokes, RANS) ensure conservation of mass, momentum and energy for a compressible fluid. Two additional equations captures the dynamics of a turbulent flow field.

Actual Geometry Analysis

Stallion 3D does not require a grid from the user because grid generation is automatic. Also, it is not necessary to defeature the geometry. This saves weeks or even months in the solution of automobile aerodynamics problems.  The unique CFD technique employed by Stallion 3D gives users a tremendous advantage over other methods because they can analyze more cases in a shorter period of time.

The Results

The following video shows how Stallion 3D solves a difficult problem. In the problem, the software accurately computes the drag on a passenger car. Accurate computations of drag is necessary for sizing engines, fuel systems and designing fuel efficient vehicles.

More information can be found at or telephone us at (352) 261-3376.

Thanks for reading.