[CFDnub]

Hello users,

I am writing a thesis on open channel axial water turbine simulation.

As for the setup, i am using transient, VOF (air and water) open channel, k-e RNG model, standard wall fn.

I have set up everything else normally such as the free surface level and boundary conditions such as pressure inlet, pressure outlet and another pressure outlet at the top surface.

For geometry,
I have 2 domains, one stationary and one rotating domain for the turbine.
Both are set with numerical beach, with the stationary domain using frame motion and the rotating domain using mesh motion with setup seen in picture.

After running the simulation the rotational domain translates from its original location to a different random location .

Can anybody advise me on this matter please, sincerely I thank you in advanced.

P.S. The yellow supposed to be the contact region between the stationary and rotating domains