[wingster77]

Hi,

I have been running propeller simulations in Fluent using the MRF (Multiple Reference Frame) method. A cylindrical domain surrounding the propeller is defined in a rotational frame of reference with respect to the surrounding stationary frame.

This method works fine and gives decent results for the thrust and torque of the propeller when the axis of the propeller is parallel to the oncoming or free-stream velocity. I have validated these simulations with experimental and other published results, for several propellers and through the entire range of advance ratio the propellers would operate at ie. at different RPM and different free-stream velocities.

However, for my application, I need to run some simulations with the axis of the propeller tilted or at a certain angle to the free-stream velocity and in this case, from literature, we expect the thrust and torque of the propellers to increase with larger angles.

But when I run these cases on Fluent using the method specified above, I seem to be getting exactly the same thrust and torque regardless of the direction of the free-stream or oncoming velocity.

Does anyone have experience with such kind of simulations? And would you be able to provide any guidance on what could be the possible issue here? Can the MRF method accurately simulate these cases?

Thanks a lot for your help!