不同形状微管道中的气体流动

不同形状微尺度管道(圆形、六边形、半圆形、不同宽高比的矩形)中的气体流动特性是微机电系统设计最为关心的问题之一.文中利用信息保存(IP)方法和直接模拟Monte Carlo(DSMC)方法进行研究,给出两种方法的计算结果相互符合,并与其它研究者的BGK模型方程计算结果进行了比较.对于微尺度管道中关心的低Mach数流动, IP方法的统计收敛效率明显优于DSMC方法.通过拟合IP和DSMC结果,给出了圆形、六边形、半圆形、不同宽高比的矩形截面情况下无量纲质量流率与等效Knudsen数的关系.

GAS FLOWS THROUGH MICRP-PIPES WITH DIFFERENT CROSS-SECTION SHAPES

The information preservation (IP) method and the direct simulation Monte Carlo (DSMC) method are employed to investigate gas flows through micro-pipes with the circular, semi-circular, hexagonal or rectangular cross sections, respectively, as an important issue in the design and optimization of MEMS devices. The IP and DSMC results agree well with each other, and are compared with the numerical solutions of the BGK model equation given by other researchers. For low Mach number cases in micro-pipe flows, the IP method demonstrates the statistically convergent efficiency superior to DSMC. The investigation shows that the cross-section shapes of micro-pipes considerately affect their mass flow rates. A relation between the mass flow rate and the equivalent Knudsen number for circular, semi-circular, hexagonal and rectangular cross sections is suggested through fitting the IP and DSMC results.