[Haeussti6]

Hello everybody,

I am currently working on a parameter study to determine the influence of turbulence intensity in the field on overall drag and got stuck with the general setup.

I am working with two regions and want to have a turbulence source term in the region two to set the turbulence level back to the same amount I have at the flow inlet of my big flow volume region one.

Region two is only very thin and its only purpose is to make sure turbulence intensity levels behind it are the same like directly after the flow volume inlet. Any other than that I don't want the flow to be influenced by the second region. Therefore I created Internal interfaces with in-place topology to upstream face, downstream face and the sides and set the region type to Fluid too. I set the same value of modified turbulent diffusivity as source term that I have at the inlet (equals a turbulence intensity of 1%). I am running my case with a Spallart-Almaras DES turbulence model.

My problem now is that even though I specify the extra source term in region two, I don't see any change in the flow field. Neither in region two itself nor in the flow field of region one where I actually want the turbulence transported to.

Is there anything I forget to check? How can I get a certain level of turbulence at a specific spot in the field without disturbing the flow?
Any feedback on a approach/idea itself is welcome too.