Particle Simulation of Rarefied Gas Flows witha Superimposed Wall Surface Temperature Gradient in Microgeometries

Authors: V. Azadeh Ranjbar

Abstract:

Rarefied gas flows are often occurred in micro electro mechanical systems and classical CFD could not precisely anticipate the flow and thermal behavior due to the high Knudsen number. Therefore, the heat transfer and the fluid dynamics characteristics of rarefied gas flows in both a two-dimensional simple microchannel and geometry similar to single Knudsen compressor have been investigated with a goal of increasing performance of a actual Knudsen compressor by using a particle simulation method. Thermal transpiration and thermal creep, which are rarefied gas dynamic phenomena, that cause movement of the flow from less to higher temperature is generated by using two different longitude temperature gradients (Linear, Step) along the walls of the flow microchannel. In this study the influence of amount of temperature gradient and governing pressure in various Knudsen numbers and length-to-height ratios have been examined.

Keywords: DSMC, Thermal transpiration, Thermal creep, MEMS, Knudsen Compressor.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1333959

References:

[1] G. E. Karniadakis, A. Beskok, N. Aluru, Microflows and Nanoflows: Fundamentals and Simulation, Springer, New York, 2005.
[2] C. Cai, I. D. Boyd, J. Fan, and F. V. Candler, "Direct simulation methods for low-speed microchannel flows", J. Thermophys. Heat Transfer 14(3)(2000), 368-378.
[3] Bird, G.A., 1976. Molecular Gas Dynamics. Clarendon Press, Oxford.
[4] G.A. Bird, Molecular Gas Dynamics and the Direct Simulations of Gas Flows, Oxford University Press (1994).
[5] Bird, G.A., 1998. Recent advances and current challenges for DSMC. Computers and Mathematics with Applications 35, 1-14.
[6] Knudsen, M. "Eine Revision der Gleichgewichtsbedingung der Gase. Thermische Molekularströmung." Ann. Phys. 31 (1910): 205.
[7] M.S, Ivanov, G.N, Markelov, S.F. Gimelshein, AIAA Paper 98-2669 (1998) .
[8] Liou, W.W., Fang, Y.C., 2000. Implicit boundary conditions for direct simulation Monte Carlo method in MEMS flow predictions. Computer Modeling in Engineering and Science 4, 119-128.
[9] Liou, W.W., Fang, Y.C., 2001. Heat transfer in microchannel devices using DSMC. Journal of Microelectromechanical Systems 10, 274-279.
[10] G. Pham-Van-Diep, D. Erwin, E. P. Muntz, Science, 245, 624 (1989).
[11] Knudsen, M. "Thermischer Molekulardruck der Gase in Röhren." Ann. Phys. 33 (1910): 1435.
[12] Young, M., Han, Y.L., Muntz, E.P., Shiflett, S. "Characterization and Optimization of a Radiantly Driven Multi-Stage Knudsen Compressor." 24th international Symposium on Rarefied Gas Dynamics. Bari, Italy, 2004.
[13] Young, M., Han, Y. L. "Aerogel as a Thermal Transpiration Membrane Material." 35th Annual SCCAVS Symposium, Anaheim, CA, 2002.
[14] E.P. Muntz, Y. Sone, K. Aoki, S. Vargo, M. Young, Performance analysis and optimization considerations for a Knudsen Compressor in transitional flow, J. Vac. Sci. Technol. A 20 (1) (2002) 214-224.
[15] C. Cercignani, Rarefied gas dynamics. From basic concepts to actual calculations, Cambridge University Press (2000).
[16] 12. Muntz, E.P. and Vargo, S.E. "Micro Scale Vacuum Pumps." The MEMS Handbook. Ed. G. Gad-el-Hak. CRC Press, 2002: 29_1-29_28.
[17] S. S. Sazhin, and V. V. Serikov, Rarefied gas flows: hydrodynamic versus Monte Carlo modeling, Planetary Sp. Sci., 45, 361-368 (1997).