热膜式气体流量传感器异物污染流场仿真分析

摘要

To study the relationship between the change of the measurement accuracy of polluted MEMS hot-film flow sensor and its polluted degree, this paper analyzes the distribution of pollutants on chip surface by experiments, establishes the schematic drawing of pollutant deposition. and uses fluent software to study. The velocity change around MEMS chip surface with pollutants. The results show that the velocity change around the chip surface with pollutants is smaller than that without pollutants. The difference of velocity increases with the increase of inlet velocity.%为研究MEMS热膜式流量传感器异物污染后的测量精度变化与污染程度的关系,通过试验分析了芯片表面污染物分布情况,建立了异物堆积模拟示意图.采用fluent流体分析软件,研究了异物堆积后MEMS芯片表面流速的变化.通过分析可知,当有异物堆积时,芯片表面附近区域流速会发生变化,比无异物堆积时变小,且速度差随入口速度的增加而增加.