压电射流角速度传感器敏感机理的有限元分析

FEM Analysis of Piezoelectric Fluidic Angular Rate's Sensitive Mechanism

采用有限元法分析了压电射流角速度传感器的敏感机理。利用ANSYS-FLOTRANCFD软件,通过建模、划分网格、加载和求解等途径,计算了在输入不同角速度时二维腔体中由喷嘴喷出气体的流场。结果表明,腔体在静止状态下,气流速度相对于腔体中心轴对称分布,两热电阻丝处的气流速度相等,两热电阻丝上的电流相等,电桥电路输出为零;在有角速度输入时,射流速度相对于腔体中心轴不再对称,两热电阻丝处的气流速度之差随着角速度而变化,引起两热电阻丝上电流之差也随之变化,电桥输出一个对应于角速度的电压。有限元计算法为压电射流角速度传感器的优化设计开辟了有效的研究途径。

In this paper, the sensitive mechanism of piezoelectric fluidic angular rate sensor is explained. Using ANSYS-FLOTRAN CFD program, the stream field of gas out of nozzles on inputting angular rate, has been obtained by a series of procedure, such as model building, meshing, loads applying and equation solving. The results are as follows: (1) In static status, the velocity of gas flow shows a symmetry distribution through central axis of enclosure. The fluid velocity at both hot wires is equal, so the current of both hot wires are also equal. The output of the Bridge circuit is zero. (2) On inputting angular rate , the velocity of jet flow shows an asymmetry distribution through central axis of enclosure. The velocity difference of gas flow at both hot wires will change with the angular rate, so lead to changing of the current difference of both hot wires. The Bridge outputs a voltage signal of corresponding to the angular rate. This calculated method provides a new road for optimization of piezoelectric fluidic angular rate sensor.