几种宽带超声物理模型换能器

SOME DIFFERENT KINDS OF THE BROAD BAND TRANSDUCERS FOR MODELLING

地质矿产部石油物探研究所

本文描述了地震物理模型中使用的几种宽带换能器的主要压电参数和技术指标。由此讨论了各种换能器的优缺点。通过简单的实验和测试表明,在实际应用中,换能器的频率特性除受压电参数影响外,还受负载阻抗的影响。选用声阻抗与负载相近的换能器,可得到更宽的频率响应。对于地震物理模型或岩石声波特性测试,使用夹心式复合PZT换能器较为理想。

In this paper, the chief piezo-electric parameters and the technical specifications of some different Rinds of the broad-band transducers for seismic modelling were described. The advantages and disadvantages of them were compared. It has been proved by experiments that in practice, the frequency characteristics of the transducer are under the influence of both the piezoelectric parameters as well as the load impedance. More broader response in frequency will be achieved by using the transducer having the approximate sonic and load impedance. In seismic physical modelling or rock sonic-character testing,the use of the sandwich structure composite PZT will be more suitable.