Specifying a rotating boundary condition

I would like to simulate a rotating wall condition.

For simplicity, imagine a square box. On the top surface of that box there is a circle. Inside of the box is a viscous fluid. I would like to impose a rotational velocity on said circle and observed the effect on the fluid inside the box.

I am defining the velocity as follows:

Ux = -(sqrt(x^2+y^2))*omega*sin(omega*t)*rect1(t[1/s])
Uy = (sqrt(x^2+y^2))*omega*cos(omega*t)*rect1(t[1/s])
Uz = 0

where omega is angular velocity.

I then apply this velocity to the circular boundary on top of the box.

I am trying to use a moving wall in my simulation but this does not seem to work. When I check my results there is no motion anywhere in the fluid or along the boundary.

Any thoughts on what I might be doing wrong?