particle deformation througn a contrained channel

Hi there,

I am doing COMSOL simulation to see the behavior of a particle flow through a microchannel. There is a area of the channel where particle size is greater than the cross section. So the particle will deform when it passes through this area. My question is to find the time that the particle takes to get through this blocking part. because i just start using COMSOL in this week. are there anybody know which physics model should i use? I am going to use two phase flow to simulate this process. But i just have a general idea. is this feasible?

Thanks in advance.