为了提高热风速风向传感器灵敏度,提出了采用低热导率衬底的方法,并利用有限元模拟和实验结果进行了验证。本文设计的传感器采用圆形结构的加热与测温电阻,利用热温差的方法测量风速和风向。为了验证传感器衬底对风速灵敏度的影响,本文分别在玻璃和陶瓷衬底上利用MEMS剥离工艺加工出了热风速传感器,并进行了风洞测试。实验结果表明,两个传感器均可以完成360°风向检测,风速量程超过10m/s。此外,通过对两组测量结果的比较可以发现玻璃衬底传感器的灵敏度比陶瓷衬底高,这与有限元模拟结果完全吻合。
In order to improve the sensitivity of thermal anemometer, this paper proposes a method for fabricating the sensor on low heat conductivity substrate. Verification was carried out by using finite element method simulation, as well as the experimental results. The circular structure sensor measures the 2-D wind speed and direction using calorimetric principle. In order to verify the influence of substrate thermal conduction on sensor sensitivity, two sensors were fabricated on glass and ceramic substrates respectively using MEMS lift-off plrocess. Wind tunnel test shows that both sensors can detect 360° wind direction and wind speed range over 10 m/s. Besides, through comparison of the two groups of test results, it can be found that the glass substrate wind sensor shows higher sensitivity than the ceramic substrate one, which is fully consistent with the FEM simulation results.