Department of Electronic Engineering, Kwangwoon University, Seoul 01897, Korea.
Sensors (Basel). 2020 Mar 31;20(7):1952. doi: 10.3390/s20071952.
We recently proposed a numerical model using equivalent circuit models to analyze the resonance characteristics of Langevin transducers and design them in a systematic manner. However, no pre-load torque biased by a metal bolt was considered in the model. Here, a parametric study is, therefore, carried out to reveal how model parameters are adapted to incorporate the pre-compression effect into our existing model. Analytical results are compared with corresponding experimental data, particularly regarding the input electrical impedance and effective electromechanical coupling coefficient for the transducer at resonance modes. The frequency response of input impedance is presented as a function of torque, both theoretically and experimentally. For 10.0 N·m bias, for instance, both resonance and anti-resonance frequencies are calculated as 38.64 kHz and 39.78 kHz, while these are measured as 38.62 kHz and 39.77 kHz by the impedance analyzer. The impedance difference between these cases is 14 Ω at resonance and 9 kΩ at anti-resonance, while the coupling coefficients in both cases become 0.238 and 0.239, respectively. Hence, these test results are closely matched with their theoretical values. Consequently, this study provides a quantitative guideline that specifies the pre-loading condition of bolt clamps with proper parameter settings to predict the intended resonance characteristics of Langevin transducers.
我们最近提出了一个使用等效电路模型的数值模型，用于分析兰杰文换能器的共振特性并以系统的方式对其进行设计。然而，该模型中没有考虑由金属螺栓产生的预载扭矩。因此，在这里进行了参数研究，以揭示模型参数如何适应将预压缩效果纳入我们现有的模型中。将分析结果与相应的实验数据进行了比较，特别是针对换能器在共振模式下的输入电阻抗和有效机电耦合系数。作为扭矩的函数，呈现了输入阻抗的频率响应，包括理论和实验结果。例如，对于 10.0 N·m 的偏置，理论上和实验上计算的共振和反共振频率分别为 38.64 kHz 和 39.78 kHz，而阻抗分析仪测量的值分别为 38.62 kHz 和 39.77 kHz。在共振时，这些情况之间的阻抗差异为 14 Ω，在反共振时为 9 kΩ，而在这两种情况下的耦合系数分别为 0.238 和 0.239。因此，这些测试结果与理论值非常吻合。因此，本研究提供了一个定量指南，规定了螺栓夹的预加载条件和适当的参数设置，以预测兰杰文换能器的预期共振特性。
