Lattice Boltzmann Modeling of Miscible Multicomponent Gas Mixtures in the Rarefied Regime  

作　　者：Michel Ho Sami Ammar Sebastien Leclaire Marcelo Reggio Jean-Yves Trepanier 

机构地区：[1]Departement of Mechanical Engineering,Polytechnique Montreal,2500 Chemin de Polytechnique,Montreal H3T 1J4,Canada

出　　处：《Communications in Computational Physics》2022年第9期1179-1216,共38页计算物理通讯（英文）

基　　金：supported by the Natural Sciences and Engineering Research Council of Canada through a grant from the Collaborative Research and Training Experience(CREATE-481695-2016)program in Simulation-based Engineering Science(Genie Par la Simulation).

摘　　要：An extension to rarefied flow regimes of the lattice Boltzmann methodbased model for miscible mixtures developed by Vienne et al.(Physical Review E 100.2(2019):023309)is presented.The model is applied to study the gas phase separation phenomenon in mixture flows that traditional macroscopic approaches fail to predict.The extension includes a wall function approach with an empirical coefficient to define an effectivemean free path in solid geometries,which locally defines the kinematic viscosity and binary diffusion coefficients.The algorithm is also modified by a local multi-relaxation time collision operator and slip boundary conditions at solid walls.Gaseous mixture flow simulations are conducted through a 2D plane microchannel within the slip and early transition flow regimes.Despite a miscible gaseous phase,the mixture loses its homogeneity and independent velocity profiles for each component are observed in the rarefied regime and captured with the current modeling.In addition,the gas separation phenomenon increases with the rarefaction rate and the molecular mass ratio.The individual treatment of the species within mixture flows in the developed lattice Boltzmann model helps understanding the increasing independent behavior of the individual specieswithin themixture as the regime becomesmore rarefied.

关 键 词：Lattice Boltzmann gaseous mixtures rarefied regimes 

分 类 号：O17[理学—数学]