阵列式压电晶体谷物损失传感器有限元分析与试验

Finite Element Analysis and Measurement for Array Piezocrystals Grain Losses Sensor

为了提高谷粒损失检测的精确度与可靠性,提出了构建压电晶体矢量传感器阵列的方案,实现参数多点实时测量。采用有限单元法对谷草撞击动力学模型进行了分析;利用ANSYS软件,根据谷粒损失传感器敏感元件的实际尺寸进行建模,计算、仿真敏感元件的振动模态,求解敏感元件谐振频率;通过分析敏感元件低阶模态的动态应变分布,确定了矢量传感器阵列中压电晶体的位置和数量,优化了阵列结构。在试验台架上进行了谷草撞击试验,使用动态信号分析仪对敏感元件的低阶振型与应变分布进行了试验测试。试验结果与理论分析结果一致,表明优化的阵列结构可用于压电晶体矢量传感器阵列的理论设计和参数修正。

In order to improve the accuracy and reliability of grain loss measuring, a scheme of constructing piezocrystal vector sensor arrays was put forward, which realized multi-point parameter real-time measurement. Kinetic model of the grain and straw impacting sensor has been analyzed by the finite element method. According to the dimension of sensitive plate, its model was created via ANSYS to compute the vibration mode and extract resonance frequency of the sensitive element. The location and the quantity of piezocrystal were identified among the vector sensor arrays by analyzing the vibration shape and distribution of dynamic strain about low order modes of sensitive element, which optimized the structure of array. The grain and straw impacting sensor was preceded on test bench. The analysis result has been compared with the measure result that obtained by the dynamic signal analyzer, the conclusion showed that the experimental results was well coincided with theory results. All these are help to devise piezocrystal vector sensor arrays for grain loss of combine and amend its parameters.