Sensitivity Analysis of Micromachined Thermal Wind Sensor Based on Back Surface Sensing Mode

This paper presents the sensitivity analysis of the micromachined thermal wind sensor based on back surface sensing mode. The effects of heating power and distance $\pmb{L}$ on the sensitivity are analyzed via simulation and experiment. $\pmb{L}$ is the length between the heater and the thermistor. Experiment has been implemented by applying three different heating power values. On the ceramic substrate, eight thermistors are divided into two groups with different distance related to the heater. The results of simulation and experiment indicate that both the increase of heating power and the distance $\pmb{L}$ can improve the sensitivity of the sensor significantly. In the constant power mode, measuring range of wind speed from 0m/s to 33m/s and full range (360°) of wind direction detection have been achieved.