新型纵径复合大功率变截面棒管式超声辐射器及关键性能研究

A new type of rod and tubular high power ultrasonic radiator with variable cross-sections in longitudinal and radial composite vibration is proposed and studied. It consists of a transducer, a barbell horn and a tube with variable cross-sections. Both the transducer and the barbell horn in longitudinal vibrations are used to drive a metal tube with variable cross-sections in a radial coupled vibration. The aim of this study is to investigate by means of its special structure vibration modes conversion a new high power ultrasonic radiator that the ultrasound can be radiated in its radial and longitudinal directions. The studies include that:(1)Based on the coupled vibration theory and the electromechanical equivalent method, the equivalent circuit of the radiator in longitudinal and radial composite vibrations is derived and the resonance frequency equation is obtained analytically, and then the relationships between the characteristics of the radiator with its geometrical dimensions and vibration modes are discussed.(2)Numerical methods are used to simulate the vibration of the radiator, and the radial and longitudinal vibrational displacement distributions, the electromechanical impedance characteristics, the radiation sound field of the radiator in the different vibration modes are obtained and discussed. Based on the analytical and numerical results, a parametric optimization method is proposed and the geometrical dimensions are optimized in order to improve the vibration and sound radiation performances of the radiator.(3)The electrometrical impedance characteristics and the vibrational displacement distributions are measured and compared with the analytical and numerical results. It is expected that this kind of ultrasonic radiator can be used in high power ultrasonic applications, and the theoretical and experimental data will be useful in the engineering applications.

提出一种新型纵径复合大功率变截面棒管式超声辐射器。该辐射器由纵振换能器、纵振哑铃型变幅棒和径向耦合振动变截面金属圆管三部分组成。项目研究的目的在于通过一个特殊的结构及振动模式转换，实现一种能够在径向、纵向同时产生大功率超声辐射的新型辐射器。研究内容包括：1、基于耦合振动理论和机电类比原理，推导此类超声辐射器的纵径复合振动的机电等效电路及共振频率方程，从理论上探讨辐射器的性能参数与其几何结构尺寸及振动模态的依赖关系。2、利用数值方法对辐射器的振动性能、机电阻抗特性及辐射声场特性进行仿真，给出辐射器的纵向、径向振动位移分布、机电阻抗特性和辐射声场与其振动模式之间的依赖关系，由此提出辐射器的参数化优化设计方法并对辐射器的各组成部分的结构尺寸参数进行优化。3、利用阻抗分析仪及激光测振仪对辐射器的机电阻抗特性、振动位移等进行实验研究。为该类辐射器在工程应用中建立较完整的理论及实验模型和优化设计方法。

本项目对一类纵径复合大功率变截面棒管式超声辐射器进行了较为系统的研究。首先，推导了该类超声辐射器纵径复合振动的机电等效电路及共振频率方程。其次，基于有限元法建立了该类超声辐射器的参数化优化设计方法，对该超声辐射器的几何结构尺寸参数进行了优化设计，在此基础上对辐射器的纵径复合振动模式及其辐射声场进行了仿真模拟及分析。随后对辐射器的共振频率、阻抗频率特性、位移振幅特性进行了仿真模拟及实验测试。理论分析及实验测试结果表明，通过特殊的结构设计及振动模式转换，可以有效增大辐射器的声辐射面积和提高其位移振幅，该纵径复合大功率变截面棒管式超声辐射器既可作为一种聚焦式超声辐射器在其管内处理液体，也可作为一种全方位径向超声辐射器在其管外处理液体。最后，提出了纵向振动变截面管形振子的一种近似解析分析方法，推导出了一种新型的纵向振动变截面管形振子的等效电路。.本项目基本按照原计划进行，并完成了计划的所有研究工作。截止目前为止，本项目共发表学术论文7篇，其中SCI期刊论文4篇、EI收录期刊论文2篇；申请专利4项，其中已授权发明专利1项和实用新型专利2项。.本项目研究结果将为新型大功率超声振动系统的理论及结构设计提供有益参考，项目研究的新型超声系统可在超声液体处理、超声提取、超声焊接及超声切割等大功率超声领域获得应用。