Different situation follows when two surfaces (c-housing.stl and c-interface.stl) have their common intersection to be caught. Utility surfaceBooleanFeatures can extract the intersection between two .stl surfaces.
In the triSurface subdirectory an .eMesh file containing edges of intersection was created. Several .obj files were created in the case directory. The one we need, to check the result visualy in paraview, is called c-housing_c-interface_intersection_edgeMesh.obj.
paraview
We can remove all the unnecessary files then.
rm -rf *.obj
Figure: Feature edges of compressor wheel (black) and intersections (red).