microfluid fluid structure interacion problem
 

Hello Everybody -
I'm trying to do a microfluid-structure interaction simulation using Ansys workbench (Workbench+CFX). The domain is composed by a 3D square (10um x 10um x 50um) drilled thru with a cone shape hole (Diameter in one side 5um and diameter in other side 2.5 um). The solid portion is loaded in the top surface with a cyclic load and fixed in the bottom surface. The fluid portion has Opening boundary conditions at each side - front and back). The idea is to study the fluid flow and behavior generated by the cyclic movement of the solid.

After doing the simulations (first the solid portion and then the fluids) I monitored the fluid flow in the two openings. Fluid flow is been conserved in time (I plotted the fluid flow at each boundary respect to time) . But when I plot the pressure and velocity at each opening I'm getting a fluctuating and INCREASING behavior. This is not normal. Additionally the V-mom imbalance is 97% (not normal as well).

Can anybody suggest a solver control configuration? or give any advise of microfluidics simulation configuration?

CFX file can be found here:
http://dl.dropbox.com/u/4171897/cone.cfx

Thanks in advance.

Santiago