Most flow phenomena in the industry are turbulent, and because of this it is important to learn about turbulence.
Different geometries will influence the turbulence in different ways. The turbulence again will influence the mechanisms for mass and heat transfer so that the transfer can be quite different for small differences in geometry.
The section has for a long time been studying turbulent motions and how they change with different boundary conditions etc. This is done partly by detailed experiments, and partly by direct solutions of the equations of motion (DNS). In this way changes down to micro scale can be found.
Surface roughness is an example of one of the effects we have been studying.