[GregM]

I am hoping that someone can point me in the right direction for debugging the following issue I have run into. I may have to make a slightly simpler geometry that I can post as an example but I have not done so yet.

The particulars: OF 2.1.1. SRFSimplefoam

The duct is one of 22 (only one is modeled) that rotate at ~140RPM about a central shaft. Inlet flow velocity is specified and is axial, non-rotating. Outlet BC is zero gradient pressure.

When I calculate the torque from the change in angular momentum of the flow field I get within ~10% of the value I was expecting from a 1D analysis. When I use the libforces.so library or calculate the torque based on the pressure forces on the moving walls using paraFoam, I get a result that is about 180% of the 1D value (the parafoam value and the libforces.so value agree exactly). I would have expected that the two methods of calculating torque from the results would be closer than that to one another. Any ideas where to start debugging this problem?

thanks