Lattice Boltzmann Flow Simulation in a Combined Nanochannel

作     者：Kazuhiko Suga Susumu Takenaka Takahiko Ito Masayuki Kaneda 

作者机构：Department of Mechanical EngineeringOsaka Prefecture UniversitySakai 599-8531Japan 

出 版 物：《Advances in Applied Mathematics and Mechanics》 (应用数学与力学进展（英文）)

年 卷 期：2010年第2卷第5期

页      面：609-625页

核心收录：

学科分类：080704[工学-流体机械及工程] 080103[工学-流体力学] 08[工学] 0807[工学-动力工程及工程热物理] 0802[工学-机械工程] 0701[理学-数学] 0801[工学-力学（可授工学、理学学位）] 

基　　金：supported financially by the Core Research for Evolutional Science and Technology(CREST)of Japan Science Technology(JST)Agency(No.228205R) the Japan Society for the Promotion of Science through a Grant-in-Aid for Scientific Research(B)(No.18360050) 

主　　题：Lattice Boltzmann method Knudsen number molecular dynamics simulation nanochannel wall boundary condition slippage velocity 

摘      要：The widely used micro-flow wall-boundary conditions for lattice Boltzmann method(LBM)are evaluated in a force driven combined nanochannel *** flow field consists of a two-dimensional nanochannel(mother channel)of an infinite length having flat plates of a finite length *** flat plate is set above the bottom wall of the nanochannel with a narrow *** flow,thus,develops through this narrow gap(narrower channel)and the other side of the plate(wide gap).The Knudsen number based on the mother channel height is Kn=0.14 whereas the characteristic Knudsen number in the narrower channel is *** obtain the reference data,the molecular dynamics(MD)simulation is performed with a fully diffusive wall *** LBMs are based on the lattice BGK model and with the bounce-back/specular reflection(BSBC)and the diffuse scattering(DSBC)wall boundary *** relaxation time is modified to include sensitivity to *** DSBC shows generally satisfactory results in the test flow cases including fully developed force driven Poiseuille flows,where the BSBC performs worse at Kn0.5 with a fixed bridge coefficient of b=*** results in its overprediction of the flow rate in the narrower channel region since the characteristic Knudsen number there is *** MD simulation suggests that the flow develops gradually through the narrower channel region though all the LBM predictions show almost instant flow *** fact suggests that the relaxation time model needs to have more sensitivity to the locally defined *** discussions of the BSBC with a different set of models suggest that the regularization process is required for predicting complex nanoscale flows.