Invited Paper VT-MoA1
Advancement in Transient Flow Simulations: Applications to Channel and Porous Media Conductance Modeling

Monday, October 21, 2019, 1:40 pm, Room A213

The gas flow through long channels of various and variable cross-sections is a practical problem in the MEMS and vacuum technology applications. As examples of such kind of flows the leakage through compressor valves and the flows in the micro bearing may be given. Among these applications, the gas flows through the low permeable membranes, which are also the flows at microscale, present also a great interest, especially in vacuum technology for filtering, separation process, protection and flow control. Recently some advancement in the transient flow simulation, based on the gas kinetic theory, was proposed in [1], [2]. Using this approach, the determination of the micro tube conductance is realized in [3]. The very similar approach is also proposed recently to characterize the permeability of the porous media like the low porous membranes [4]. Different examples of application of the proposed methodology will be shown for various type of porous media et different gases under isothermal and non-isothermal conditions.

References:

[1] F.Sharipov, I.Graur, General approach to transient flows of rarefied gases through long capillaries, Vacuum, v100, pp.22-25, 2014

[2] Graur, M.T. Ho, Rarefied gas flow through a long rectangular channel of variable cross-section, Vacuum, 101, 328-332, 2014.

[3] M. Rojas-Cardenas, E. Silva, M.-T. Ho, C. J. Deschamps, I. Graur, Time-dependent methodology for non-stationary mass flow rate measurements in a long micro-tube: Experimental and numerical analysis at arbitrary rarefaction conditions, I. Microfluid Nanofluid (2017) 21: 86.

[4] M.V. Johansson, F. Testa, I. Zaier, P. Perrier, J.P. Bonnet, P. Moulin, I. Graur, Mass flow rate and permeability measurements in microporous media, v 158, Vacuum, 2018, pp. 75-85