Bem For The Analysis Of Fluid Flowaround Mems.

Abstract

The boundary element method (BEM) is used in this work for modelling the fluid flow
around a vibrating micro-electro-mechanical system (MEMS). Device motion induces flow and, therefore,
drag-forces develop on the surface of the MEMS with a damping effect on the MEMS vibration.
We assume that the fluid around MEMS can be treated as a continuum and, further on, that the flow can
be modelled as incompressible with a very low Reynolds number. Under such conditions, met in a large
number of MEMS in practice, the fluid flow can be accurately described by Stokes theory of quasi-steady
incompressible flow. We take into account MEMS deformation effects on fluid flow analysis.
Fast integration is performed using the collocation method. Self-integrals containing singular kernels
are analytically computed over linear triangles.
This model has been computationally implemented into the engineering software OOFELIE:MEMS,
developed by Open Engineering SA.
The accuracy of the model is tested using a benchmark problem – the flow around a sphere moving
with constant velocity–, with satisfactory results. Preliminary results of an application to MEMS are also
shown.