Influece of wall velocity in the main flow

marvin

I'm a little confused about the effect of moving wall in the velocity profile. I compared 2 models (single fluid incompressible in a pipe using k-epsilon model & smooth wall), one has wall velocity and the other has fixed wall. Based on the results, the velocity profiles from the center up to a point near the wall are almost identical for both cases. And from that point up to the wall, the velocity goes to zero (for fixed wall) and the other suddenly converges to the given wall velocity. It means that the wall velocity doesn't influence the main flow and it only affects near the wall. Is this correct? Someone told me that the result should be something like you add the wall velocity to the results of a fixed wall which is I'm having a hard time to visualize. Pls. help me guys!Enlighten me please!

Thanks a lot!