高静水压下障板样品声特性的计算与测量

为研制一种在声呐水下声系统中起到屏蔽噪声、提高声基阵空间增益作用的耐压、低频、宽带声障板,设计了声管样品,根据分层介质中的声传播理论,利用多层均匀结构的传递矩阵法计算了它在空气和水介质背衬下的声压反射系数和透射系数,在不同的背衬情况下具有明显不同的声学特性。制备了直径206mm的样品,利用杭州应用声学研究所水声驻波管和行波管测量系统测量了频率范围100Hz～4kHz、静水压范围从常压到2MPa的声学性能,测量结果和理论计算值基本吻合,声障板样品在静水压状态下具有一定的低频、宽带反声特性。

Calculation and Measurement for Acoustic Characteristics of Baffle Sample under High Hydrostatic Pressure

In order to develop a pressured, low-frequency and wide-band acoustic barrier which can shield the noise and improve the spatial gain of acoustic array in underwater sonar system, the acoustic tube sample was designed. According to the sound propagation theory in layered medium, the sound pressure reflection coefficient and transmission coefficient under the backing of air and water were calculated by using the transfer matrix method of multilayer uniform structure, and there were obvious different acoustic properties. A measured sample with a diameter of 206mm was made. The acoustic performance of the acoustic baffle sample in the frequency range of 100Hz～4kHz and the hydrostatic pressure range from normal pressure to 2MPa was tested by using the standing wave tube and traveling wave tube measurement system in Hangzhou Research Institute of Applied Acoustics. The measured results are basically agreed with the theoretical calculation value. The acoustic baffle sample has certain low-frequency and wide-band echo characteristics under hydrostatic pressure.