70 Meter Satelite Dish in a Breeze

Just a 70m satelite dish in a slight 25m/s breeze. “Colourful” fluid dynamics (CFD) with the openfoam.com toolchain of snappyHexMesh, simpleFoam and paraview.

Also needed to repair the model in blender and FreeCad. We really enjoy working with this opensource toolchain to provide automated solutions to our customers engineering teams. These screenshots were the result of a quick test to see how well the current version of snappyHexMesh performs with poor model quality and when spanning several orders of magnitude of relevant feature sizes.

Here is a view of the backside truss structure of the satelite dish. NASA has a repository of their 3-D models over at github which includes this model. The dish diameter is 70m, the truss structure is massive, but compared to the dish diameter the individual trusses are relatively small. Depending on the angle of attack they may contribute significantly to the total drag. Ultimately, the important parameter is the dish shape, and the deformation under wind load determines the operational envelope. This is a nice test case because the relevant feature sizes span several orders of magnitute. Models like these are challenging to mesh, and to properly resolve.