Hi, I'm trying to model air and water flow around a car tire on a wet track.say there is a 10 mm thickness of water on the ground and 40 mm air on the top.so,my domain is 50mm height with two inlets.The ground is moving and the tire is fixed(no rotation).Water and air approachs the tire at say 15 m/s velocity.what i need to know frm this problem is how the water flows around the tire at time steps.So,What is boundary condition and initial condition I can use to model this. Thanks.