An improved thermal lattice Boltzmann model for rarefied gas flows in wide range of Knudsen number
An improved thermal lattice Boltzmann model for rarefied gas flows in wide range of Knudsen number
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DOI：
10.1016/j.icheatmasstransfer.2011.08.009
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发表时间：
2011-12
影响因子：
7
通讯作者：
H. Shokouhmand;A. H. Isfahani
中科院分区：
文献类型：
--
作者：
H. Shokouhmand;A. H. Isfahani
为了能覆盖更宽的流型范围，考虑到稀疏效应对粘性和导热系数的影响，提出了一种新的格子Boltzmann方法（LBM）的弛豫时间公式。为了验证所提出的模型，充分发展的压力驱动流和发展的微/纳米通道中的热流进行了建模。结果表明，在较宽的Knudsen数范围内，修正后的热LBM得到的速度、温度分布、体积流量和局部Nusselt数与其它数值和经验结果吻合较好.
In order to covering a wide range of the flow regimes, a new relaxation time formulation for the lattice Boltzmann method, LBM, by considering the rarefaction effect on the viscosity and thermal conductivity has been presented. To validate the presented model, fully developed pressure driven flow and developing thermal flow in micro/nano channel have been modeled. The results show that in spite of the standard LBM, the velocity and temperature distributions, the volumetric flow rate and the local Nusselt number obtained from this modified thermal LBM, agree well with the other numerical and empirical results in a wide range of Knudsen numbers.