Hello, I am working on a sudden valve closure effect in pipeline, also known as the water hammer. I have to use Fluent to get the velocity profile, the shear stress distribution and the pressure contour in the pipe when the pressure pulse will go through the fluid. To model the valve closure I try to use the sliding mesh capabilities of Fluent. I was thinking about having two parts for the pipe (before and after the valve), an interface between the two zones and a sliding mesh at this interface. However it does not look like working. Would someone indicate me a possible mistake in the methodology and/or indicate a good source to learn more about the sliding mesh. Thank you for your help.