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出现于８０年代后期的微机械工艺技术可提供微米尺度的传感器和致动器．这些微型转换器与信号调节和处理电路集成后，组成了可执行分布式实时控制的微电子机械系统（ＭＥＭＳ）．这种性能为流动控制研究开辟了一个崭新的领域．另一方面，由于微米尺度结构中表面积与体积之比很大，在流体流经这些微小机械器件时，表面效应占据了主导地位．为此需要重新审视动量方程中的各类表面力项．由于它们非常小，气体流动具有很大的Ｋｎｕｄｓｅｎ数，所以边界条件也应加以修正．总之，微电子机械系统（ＭＥＭＳ）不但是一项实用技术，也为流动机理的基础研究提出了许多挑战．
Micromechanical processes that emerged in the late 1980s provide sensors and actuators on the micrometer scale. Integrated into the signal conditioning and processing circuitry, these micro-converters comprise a microelectromechanical system (MEMS) that performs distributed, real-time control. This kind of performance has opened up a brand-new field for the research of flow control. On the other hand, due to the large surface area to volume ratio in microscale structures, the surface effect dominates as fluid flows through these tiny mechanical devices. To do this, we need to re-examine all kinds of surface force in momentum equation. Since they are very small and the gas flow has a large Knudsen number, the boundary conditions should also be corrected. In summary, microelectromechanical systems (MEMS) are not only a practical technique, but also pose many challenges for basic research on flow mechanics.