Hanley Innovations developed Stallion 3D for rapid aerodynamics analysis of three-dimensional solid models. This software is a quick and inexpensive option to perform aerodynamic conceptual analysis on a 3-dimensional CAD model without the time-consuming ritual of grid generation. The analysis can be performed on your desktop computer or laptop.
The following steps can be followed to determine the lift and drag on a road vehicle.
|Stallion 3D Main Window|
|A car from Turbosquid.com as seen in Stallion 3D.|
The .stl input box also allow you to rotate and translate the part. This allows you to point the leading edge of the model (longitudinal direction) along the x-axis and the lateral direction along the y-axis.
|The .stl dialog box can be used to orient the model.|
Before exiting the .stl import box, you can also explore the options to scale the model and set the correct dimensions. The default in Stallion 3D is meters, however, you can select inches, feet and cm.
|Scale and dimension the solid model.|
|The design editor window can be used to add wings and other components to the model.|
|The user can choose the problem size. A quick run is helpful to test the setup.|
|Set the flow domain dimensions to simulate the physics and facilitate convergence.|
|Set the lower boundary as reflective (instead of radiative) to simulate the road.|
The next step in the solution is to set the flow speed and reference areas and lengths for the lift, drag and moment computations.
Finally, simply click the CFD Solver menu and select Generate Grid/Solve flow. The program will automatically generate the grid and launch the flow solver. For this specific problem, the grid generation took about 20 - 30 minutes on my laptop. The algorithm generated 132,833 nodes.
Once the grid was generated, the flow solver started to solve the 3-dimensional compressible Euler equations (with the low speed flow option). The solver computes the lift, moments and pressure drag for the 3-dimensional configuration with good accuracy. Stallion 3D can also solve the 3-D Navier-Stokes equations for the same configuration.
|The flow solver updates 132,833 nodes every iteration using a 4-stage Runge-Kutta method.|
|Pressure on the surface of the car.|
|Velocity on the surface of the car.|
|Velocity at the ground plane.|
|Computed lift, drag and moment coefficients based on vehicle frontal area.|
More information about Stallion 3D can be found at http://www.hanleyinnovations.com/
Thanks for reading.