The GASMEMS network: Rationale, programme and initial results

Abstract

GASMEMS is an Initial Training Network supported by the European Commission, which aims at training young researchers in the field of rarefied gas flows in MEMS, and at structuring research in Europe in the field of gas microflows in order to improve global fundamental knowledge and enable technological applications to an industrial and commercial level. The partners and the global objectives of this 4 year programme are detailed, and some initial results are presented. First experimental data about the flow of binary gas mixtures through rectangular microchannels are successfully compared with continuum and kinetic models, in the slip flow and early transition regimes. The behaviour of these mixtures has also been simulated in triangular microchannels, for the whole range of the Knudsen number, using a kinetic approach and the McCormack model. Heat transfer in plane microchannels has been numerically investigated, pointing out compressibility and rarefaction effects. The effect of thermal creep has been studied comparing BGK, Smodel and ellipsoidal model with the solution from the full Boltzmann equation. A semi-analytical model of the Knudsen layer has been developed and used to simulate the problem of thermal transpiration in a microchannel. Gaseous flows through rough microchannels have been simulated using kinetic theory and DSMC method, the wall roughness being simulated as a highly porous medium of variable thickness.