multiphase model

Mavinakere

Hi, I'm simulating multiphase model of hydroplaning tire using air and water.now,i'm calculating the steady flow using VOF option and i found the pressure distribution matching with the experimental value but the lift forces dont seem to match....isn't it strange??? my question is...while you find lift forces on the tire should you consider 1) the part of the tire which is in contact with water using the reference values for the water density and velocity of water and the area of the tire in contact with water. 2)plus the part of the tire which is in contact with air using the reference values for the air density and velocity of air and the area of the tire in contact with air anybody plz give me some suggestions on this,because i'm confused that i'm getting good pressure distribution around the tire but not the lift forces. thanks in advance. Mavinakere.