应用BGK格式数值模拟微槽道中的气体流动

Numerical simulation of gas flows in micro-channels with the GBK scheme

基于BGK-Boltzmann模型方程的气体运动论数值算法,对不同Knudsen数下、压力驱动的二维微槽道流动进行了数值模拟,目的在于将BGK格式拓展应用于对微流动(常密度、流动Kn较大)的数值计算。通过BGK数值模拟结果与N-S方程加滑移边界修正的解析解以及MonteCarlo直接数值模拟(DSMC)结果的对比,揭示了BGK方法具有模拟结果良好并且计算经济的特点;结合以前的工作,可初步认为BGK在解决Knudsen数相对较大(0.1<Kn<1.0)的流动问题方面,具有很好的可行性。

Boltzmann gas kinetic theory, BGK was used to numerically simulate pressuredriven gas flow in 2D microchannels at various Kn numbers. The BGK scheme was extended to simulate the microflows, which have constant densities but comparatively large Kn numbers. Compared with other numerical methods, such as NS equations with slipboundary modification and direct simulation of Monte Carlo (DSMC) method, the BGK scheme was found to be more efficient while still being accurate. Therefore, combining former research the BGK scheme can be considered to efficiently and accurately solve flow problems with comparatively large Kn numbers (0.1<Kn<1.0).