Oscilating rotation using a multiphase tank
 

Hi,

I'm using Ansys Cfx to simulate a tank rotating about the Z axis with specific anglular velocity/frequency. The tank contains fractions of water and air with no opening. I am using a transient analysis. When setting up the problem I can choose a rotating domain with a specified angular velocity but this only rotates the the tank in one direction. I want to rotate the tank backwards and forwards with a specified angular velocity. Is there anyway of doing this or is the best way to write an expression and put it into the angular velocity space in domain motion? Any help is appreciated.

Thanks,
Jim