[keg504]

Hi all,

I'm trying to run steady state simulations of a propeller in steady state with an oncoming wind of 17 m/s. I have two regions/domains, a rotating one (I setup a rotating reference frame under tools with the intended rotation rate) and a stationary domain, with symmetry for a 2 bladed propeller. I have ~5.6 million cells with a polyhedral mesh, prism on the blade and the hub. The hub is a slip wall, while the blade is a no-slip wall.

The blade is subtracted from the rotating region after a surface wrap (the original STL is not watertight). I'm getting strange results for the simulation, and I'm very confused about the boundary conditions. I have a velocity inlet with 17 m/s, set component-wise. The outlet is an outlet condition, and the opening to the air is set as a pressure outlet. I have an example case that converges well (all residuals in order of 1e-06) that I'm trying to not replicate, but use as a basis for my analysis, and it sets the opening to a freestream boundary condition. That causes my x-momentum residuals not to converge at all, and the expected thrust is 2/5 of what is expected from BEMT.

What are the correct boundary conditions? I have done a static thrust analysis of propellers in CFX, and that had an opening boundary condition, but now I get reversed flow that the opening boundary condition solved well.
I have attached velocity and residual plots. I will send a mesh plot later after I get more iterations of the simulation and stop it.

StarCCM plots 1.png

Edit: Here is the mesh plot

image (1).png