Hostname: page-component-586b7cd67f-l7hp2 Total loading time: 0 Render date: 2024-11-26T06:13:47.805Z Has data issue: false hasContentIssue false

An Efficient Hybrid DSMC/MD Algorithm for Accurate Modeling of Micro Gas Flows

Published online by Cambridge University Press:  03 June 2015

Tengfei Liang*
Affiliation:
Department of Mechanical Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
Wenjing Ye*
Affiliation:
Department of Mechanical Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong KAUST-HKUST Micro/Nanofluidic Joint Laboratory, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
Get access

Abstract

Aiming at simulating micro gas flows with accurate boundary conditions, an efficient hybrid algorithm is developed by combining the molecular dynamics (MD) method with the direct simulation Monte Carlo (DSMC) method. The efficiency comes from the fact that the MD method is applied only within the gas-wall interaction layer, characterized by the cut-off distance of the gas-solid interaction potential, to resolve accurately the gas-wall interaction process, while the DSMC method is employed in the remaining portion of the flow field to efficiently simulate rarefied gas transport outside the gas-wall interaction layer. A unique feature about the present scheme is that the coupling between the two methods is realized by matching the molecular velocity distribution function at the DSMC/MD interface, hence there is no need for one-to-one mapping between a MD gas molecule and a DSMC simulation particle. Further improvement in efficiency is achieved by taking advantage of gas rarefaction inside the gas-wall interaction layer and by employing the “smart-wall model” proposed by Barisik et al. The developed hybrid algorithm is validated on two classical benchmarks namely 1-D Fourier thermal problem and Couette shear flow problem. Both the accuracy and efficiency of the hybrid algorithm are discussed. As an application, the hybrid algorithm is employed to simulate thermal transpiration coefficient in the free-molecule regime for a system with atomically smooth surface. Result is utilized to validate the coefficients calculated from the pure DSMC simulation with Maxwell and Cercignani-Lampis gas-wall interaction models.

Type
Research Article
Copyright
Copyright © Global Science Press Limited 2014

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

[1] Leung, R., Cheung, H., Gang, H. and Ye, W., A Monte Carlo Simulation approach for the modeling of free-molecule squeeze-film damping of flexible microresonators, Microfluid. Nanofluid., 9(2010), 809818.Google Scholar
[2] Ohwada, T., Sone, Y. and Aoki, K., Numerical analysis of the Poiseuille and thermal transpiration flows between two parallel plates on the basis of the Boltzmann equation for hard-sphere molecules, Phys. Fluids A, 1(1989), 2042.Google Scholar
[3] Ohwada, T., Sone, Y. and Aoki, K., Numerical analysis of the shear and thermal creep flows of a rarefied gas over a plane wall on the basis of the linearized Boltzmann equation for hard-sphere molecules, Phys. Fluids A, 1(1989), 1588.CrossRefGoogle Scholar
[4] Sone, Y., Ohwada, T. and Aoki, K., Temperature jump and Knudsen layer in a rarefied gas over a plane wall: Numerical analysis of the linearized Boltzmann equation for hard-sphere molecules, Phys. Fluids A, 1(1989), 363.CrossRefGoogle Scholar
[5] Xu, K. and Huang, J. C., A unified gas-kinetic scheme for continuum and rarefied flows, J. Comput. Phys., 229(2010), 77477764.CrossRefGoogle Scholar
[6] Xu, K. and Huang, J. C., An improved unified gas-kinetic scheme and the study of shock structures, J. Inst. Math. Its Appl., 76(2011), 698711.CrossRefGoogle Scholar
[7] Rapaport, D. C., The Art of Molecular Dynamics Simulation. Cambridge Univ Pr, 2004.Google Scholar
[8] Bird, G. A., Molecular gas dynamics and the direct simulation of gas flows, 1994.Google Scholar
[9] Maxwell, J. C., On stresses in rarified gases arising from inequalities of temperature, Philos. Trans. R. Soc. London, 170(1879), 231256.Google Scholar
[10] Cercignani, C. and Lampis, M., Kinetic models for gas-surface interactions, Transp. Theory Stat. Phys., 1(1971), 101114.Google Scholar
[11] Arkilic, E. B., Breuer, K. S. and Schmidt, M. A., Mass flow and tangential momentum accommodation in silicon micromachined channels, Fluid, J. Mech., 437(2001), 2943.Google Scholar
[12] Ewart, T., Perrier, P., Graur, I. and Molans, J. G., Tangential momemtum accommodation in microtube, Microfluid. Nanofluid., 3(2007), 689695.CrossRefGoogle Scholar
[13] Agrawal, A. and Prabhu, S., Survey on measurement of tangential momentum accommodation coefficient, J. Vac. Sci. Technol., A, 26(2008), 634.Google Scholar
[14] Bruno, D., Cacciatore, M., Longo, S. and Rutigliano, M., Gas-surface scattering models for particle fluid dynamics: a comparison between analytical approximate models and molecular dynamics calculations, Chem. Phys. Lett., 320(2000), 245254.Google Scholar
[15] Yamamoto, K., Takeuchi, H. and Hyakutake, T., Characteristics of reflected gas molecules at a solid surface, Phys. Fluids, 18(2006), 046103.CrossRefGoogle Scholar
[16] Yamamoto, K., Takeuchi, H. and Hyakutake, T., Scattering properties and scattering kernel based on the molecular dynamics analysis of gas-wall interaction, Phys. Fluids, 19(2007), 087102.CrossRefGoogle Scholar
[17] Masters, N. D., Ye, W. and King, W. P., The impact of subcontinuum gas conduction on topography measurement sensitivity using heated atomic force microscope cantilevers, Phys. Fluids, 17(2005).Google Scholar
[18] Zhu, T. and Ye, W., Origin of Knudsen forces on heated microbeams, Phys. Rev. E, 82(2010), 036308.Google Scholar
[19] Gupta, N. K., Masters, N. D., Ye, W. and Gianchandani, Y. B., Gas flowin nano-channels: Thermal transpirationmodelswith application to a si-micromachinedknudsen pump, in Transducers ‘07, Int. Conf. Solid-State Sens., Actuators Microsyst., 2007, 23292332.Google Scholar
[20] Nedea, S., Frijns, A., Steenhoven, A. van, Markvoort, A. and Hilbers, P., Hybrid method coupling molecular dynamics and Monte Carlo simulations to study the properties of gases in microchannels and nanochannels, Phys. Rev1. E, 72(2005), 016705.Google Scholar
[21] Gu, K., Watkins, C. B. and Koplik, J., Atomistic hybrid DSMC/NEMD method for nonequilib-rium multiscale simulations, J. Comput. Phys., 229(2010), 13811400.Google Scholar
[22] Barisik, M., Kim, B. and Beskok, A., Smart wall model for molecular dynamics simulations of nanoscale gas flows, Commun. Comput. Phys., 7(2010), 977993.Google Scholar
[23] Barisik, M. and Beskok, A., Equilibrium molecular dynamics studies on nanoscale-confined fluids, Microfluid. Nanofluid., 11(2011), 269282.CrossRefGoogle Scholar
[24] Yamamoto, K., Slip flow over a smooth platinum surface, JSME Int. Ser, J.,. B, 45(2002), 788795.Google Scholar
[25] Satake, S., Inoue, N., Kunugi, T., Shibahara, M. and Kasahara, H., Large-scale molecular dynamics simulation for two Ar clusters impact on 4H-SiC, Nucl. Instrum. Methods Phys. Res., Sect. B, 257(2007), 639644.Google Scholar
[26] Zeppenfeld, P., David, R., Ramseyer, C., Hoang, P. N. M. and Girardet, C., Adsorption and structure of N2 on Pt(111), Surf. Sci., 444(2000), 163179.CrossRefGoogle Scholar
[27] Barisik, M. and Beskok, A., Boundary treatment effects on molecular dynamics simulations of interface thermal resistance, J. Comput. Phys., 231(2012), 78817892.CrossRefGoogle Scholar
[28] Gupta, N. K. and Gianchandani, Y. B., A knudsen pump using nanoporous zeolite for atmospheric pressure operation, in Micro Electro Mech. Syst., IEEE Int. Conf., 21st, 2008, 3841.Google Scholar
[29] Sharipov, F., Application of the Cercignani-Lampis scattering kernel to calculations of rarefied gas flows. III. Poiseuille flow and thermal creep through a long tube, European Journal of Mechanics, B: Fluids, 22(2003), 145154.Google Scholar
[30] Sazhin, O., Kulev, A., Borisov, S. and Gimelshein, S., Numerical analysis of gas-surface scattering effect on thermal transpiration in the free molecular regime, Vacuum, 82(2007), 2029.Google Scholar