微管道气体流动  

GAS FLOWS IN A MICROTUBE/MICROCHANNEL

作　　者：孙德军[1] 秦丰华[1] 尹协远[1] 

机构地区：[1]中国科学技术大学力学和机械工程系,合肥230026

出　　处：《机械强度》2001年第4期460-464,共5页Journal of Mechanical Strength

基　　金：国家自然科学基金资助项目 (1 970 2 0 1 7)

摘　　要：对于长微管道气体流动 ,得到了简化的控制方程组 ,采用迭代方法可以给出流动的速度分布、密度分布 ,进而求出质量流量。实验研究表明 ,简化计算得到的流量基本上是合理的 ;即使对于极低的Mach数流动 ,微尺度流动的可压缩效应也十分明显。蒙特卡洛直接数值模拟表明 ,随着Knudsen数的增加 ,稀薄气体效应增强 ,滑流解与直接数值模拟的解偏差增大 。For the gas flow in a long microtube, the general numerical methods, such as DSMC, encounter difficulties due to the enormous length-diameter ratio. A simplified system of control equations is derived for slip flow in a long microtube, and then an iterative method is used to solve the equations combined with slip boundary conditions on the solid wall to give the distribution of flow velocity, density, and thus the mass flow rate. The experimental study shows that: The mass flow rote obtained by the simplified computation is rational at Knudsen numbers 3 × 10-3 [similar to] 7 × 10-3; The compressibility of microscale flow is obvious even though the Mach number is very small. The DSMC study of gas flow in a microchannel reveals that the rarefied gas effect enhances, and the difference between the slip flow solution and the result of DSMC becomes larger as the Knudsen number is increased. Therefore the slip flow solution is not accurate for microscale flow at such Knudsen numbers.

关 键 词：微管道 可压缩效应 稀薄气体效应 Knudsen数 质量流量 气体流动 微电子机械系统 

分 类 号：TH－39[机械工程] O35[理学—流体力学]