收发合置水声管中使用宽带脉冲的吸声测量方案

An improvement scheme of broadband sound absorption measurement in water-filled impedance tube with monostatic transducer

水声管是水声材料吸声测量的重要实验平台。对于收发合置换能器水声管系统,目前常用的吸声测量信号是调制正弦信号。为了实现宽带测试,提出了水声管中宽带声脉冲的产生方法,并设计了电子开关延时控制电路。给出了基于收发合置型换能器水声管中宽带吸声测量结果。

Water-filled impedance tube is an important platform for sound absorption measurement. For the test system with monostatic transducer, the common used signal is the pulse modulated sine-wave, which is essentially a single frequency measurement. In order to implement broadband sound absorption measurement, an impulsive sound is generated in water-fried impedance tube, and a time sequence control system is designed for the monostatic transducer generating the impulsive sound and picking up the echo-signal. The principle of sound absorption measurement is ex- plained and a test example is shown.