浮动电容式剪应力微传感器结构设计解析模型

为提高设计水平和效率,建立了浮动电容式剪应力微传感器结构设计解析模型。该解析模型明晰了微传感器探头结构参数与传感器性能指标之间的关系。针对微传感器量程、固有频率、非线性度、灵敏度和分辨率等指标需求,能够更有针对性地快速得到优化传感器结构方案。结合设计案例,给出了微传感器探头结构的设计方法与流程,设计研制的传感器测试实验结果与解析模型的设计结果相符合。

Analytical model for structure design of floating element wall shear stress micro-sensor with capacitive sensing

The capacitive sensor with a micro floating element can measure the wall shear stress in the flow boundary layer directly. The sensor output voltage is linear to the applied wall shear stress and it is much more precise than conventional methods. We built up the analytical model for the sensor design by studying how structural parameters influence the sensor performances. The sensor consists of a floating element, folded tethers, movable comb fingers, fixed comb fingers and anchors, etc. And the sensor performances include measurement range, natural frequency, nonlinearity, sensitivity and resolution. The relationships between structural parameters and sensor performances are clarified explicitly by the analytical model. And the micro-sensor design becomes much easier and more efficient. Static and dynamic calibration were carried out and the results indicate a good agreement with predictions of the analytical model.