Pressure Drops of Water Flow Through Micromachined Particle Filters

When the particle is in the order of microns, flow through the small opening produces a large velocity gradient, leading to high viscous dissipation. Understanding the flow field is critical in determining the power requirement. In this paper, we studied water flow through filters fabricated by micro-electro-mechanical system (MEMS) techniques. The pressure drop calculated by a three-dimensional numerical code of the Navier-Stokes equations is in a resonable agreement with the experimental data if the diameter and the side wall profile of the holes are measured with high accuracy.