构建了微尺度条件下含黏性热耗散和压力功的总能形式的双分布函数格子Boltzmann (LB)模型，计算并分析了恒壁温与恒热流边界条件下，稀薄效应对速度驱动的平直微通道内气体流动与传热特性的影响.结果表明：在不同的热边界条件下，稀薄效应对微通道内气体流动特性的影响一致，即均使得气体流速增大，通道摩擦系数减小；由于气体温度场分布的差异，使得稀薄效应对气体传热特性的影响截然不同，在恒壁温边界条件下气体传热特性有所提高，而在恒热流边界条件下气体传热特性有所减弱.
The micro total-energy-based double-distribution-function lattice Boltzmann (LB) model with viscous dissipation and compression work was developed to simulate the gaseous flow and heat transfer in a microchannel with uniform wall temperature boundary condition and uniform heat flux boundary condition. The rarefaction effect on gaseous flow and heat transfer characteristic was studied intensively for different uniform Knudsen numbers. The numerical results show that the rarefaction effects on gaseous flow with these two thermal boundary conditions are similar，which can increase the gaseous flow velocity and reduce the friction coefficient. However, due to the different temperature distributions caused by different boundary conditions, the rarefaction effect will have different influences on the heat transfer characteristics. The heat transfer process is enhanced with uniform wall temperature boundary condition and deteriorated with uniform heat flux boundary condition, respectively.
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