System level model of damping effects for highly perforated torsional microstructures

We propose a mixed-level simulation scheme for squeeze film damping (SQFD) effects in microdevices, which makes it possible to include damping effects in system-level models of entire microsystems in a natural, physical-based, and flexible way. Our approach allows also for complex geometries, large deflections and coupling to other energy and signal domains. Applying the methodology to torsional structures yields results which are in excellent agreement with accurate FEM simulations based on the 3D Navier-Stokes equations, thus demonstrating the practicality and quality of our approach. For device geometries with densely distributed perforations we propose a further order reduction by merging adjacent holes in one equivalent network element; in this way we are able to simulate highly perforated structures at affordable computational expense. The predictive simulation of an industrial microrelay featuring 3000 perforations validated by experimental analysis, illustrates the power of our methodology.