前盖板开矩形通孔型宽带换能器

提出一种利用多模态耦合的开孔型宽带换能器。在传统纵振换能器前盖板一定距离处开一矩形通孔,以激发出能与纵振耦合从而拓宽频带的振动模态。以带宽为目标,利用有限元方法对通孔的长度、宽度和孔前端离前盖板端面的距离进行了优化设计,得到了最佳的开孔位置和尺寸。研制了换能器样机。测试结果表明,在12~32 kHz频带范围内,换能器有3个工作模态,后两阶模态对工作带宽的展宽有贡献。未开孔的同尺寸纵振换能器-3 dB带宽仅3 kHz,开孔换能器带宽则达10.50 kHz,有效地拓展了工作带宽。理论计算和测试结果吻合较好。 

A wideband transducer with a rectangular hole in the front head

An open-hole broadband transducer using multi-mode coupling is proposed.A rectangular through hole is opened at a certain distance from the front cover of the traditional longitudinal vibration transducer to excite the vibration mode that is coupled to the longitudinal vibration and is beneficial to broaden the frequency band.state.The factors that affect the working bandwidth of this kind of transducer include the length and width of the through hole and the distance between the front end of the hole and the end surface of the front cover.The finite element method is used for structural optimization design and vibration radiation characteristics analysis to obtain the best opening size.The transducer prototype was made.The test results show that the transducer has three main operating modes within 12-32 kHz,and the latter two modes contribute to the widening of the operating bandwidth.The test results show that the-3 dB bandwidth of the same size longitudinal vibration transducer without a hole is only 3 kHz,and the corresponding maximum transmitting voltage response is 148 dB,while the holed transducer has a bandwidth of 10.5 kHz and a maximum transmitting voltage response value of 141 dB.It obviously expands the bandwidth.The theoretical calculations and experimental results are in good agreement.In addition,the holed transducer proposed in this work maintains the evenness of the face of the front head,and compared with the same size longitudinal vibration transducer,its front face will also have a larger amplitude,which can be effectively applied in civil fields such as ultrasonic cleaning.