"Unsteady Rarefied Flow Simuations in N/MEMS"
November 18 @ 3:00 PM - 4:00 PM - Birck 1001
Further development of high- frequency microsystemssuch as resonators, RF MEMS, microturbinesand pulsed-detonation microenginesrequire improved understanding of unsteady gas dynamics at the microscale. At the microscale, the continuum equations tend to breakdown when the Knudsen number is greater than 0.1 and a model at the molecular level is required. And Direct Simulation Monte Carlo (DSMC) methods are very computationally expensive for such low speed unsteady near-continuum flows. In her thesis, Sruti formulated a fully deterministic finite volume based approach for solution of ES-BGK Boltzmann model kinetic equation with conservative discrete-ordinate velocity method to enable simulations of unsteady 3D rarefied flows in complex geometries. Sruti incorporated the rarefied flow formulation into MEMS Overall Simulation Administrator (MEMOSA), the solver developed by PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems at Purdue. In this talk, Sruti will concentrate on verification and validation of this parallel solver and application to the unsteady micro-scale gas damping in MEMS switches with opening and closing gaps. This solver has the added advantage of easy coupling to other deterministic solvers such as the Navier-Stokes equations and other structural solvers.
- Bonnie Kauffman