Solver setting in microfluidics simulation
 

I am simulating fluid field of a micromixer created by nanomotor. The motor rotate in speed range from 10rad/s to 100 rad/s, speed is sinel, I can simplify it as a constant. I confine the nanorod (300nm in diameter and 10 um in length) in a fluid channel with a width of 20 um and simulate the velocity field. I use the sliding mesh method. The initial condition is "all 0 in all zones", Does it make sense?
I have a question. Which solver model should I use? and what else should I notice about setting up ?