This tutorial illustrates how to solve a three-dimensional compressible flow problem using STAR-CCM+. The geometry in question is a NACA-type axisymmetric inlet in a free-stream air flow of Mach 0.21. The flow captured by the inlet is forced into an S-bend before reaching the engine face.
It should be noted that, in order to keep the cell count low for this case, certain compromises have been made. Even though the case is run turbulent for this exercise, the mesh is really more suited for inviscid flow. Because no attempt is made to resolve the boundary layers, the results are thus essentially what one would obtain from an inviscid simulation. This is not a recommended practice for most simulations.
In addition, the mesh has been created in three separate non-conformal sections. This enables the tutorial to illustrate a useful feature of STAR-CCM+, the ability to "fuse" separate mesh sections into a contiguous mesh.
In spite of the fact that the mesh is too coarse to produce a mesh-independent solution, the simulation results are shown to compare favorably with experimental data for pressure on the S-duct walls.
The mesh used for this intake example is based on an S-duct inlet mesh from NASA.