水下材料吸隔声性能测试近场长脉冲传递函数法

为消除有限空间壁面反射对大样水下材料声学性能测试的影响，利用传递函数法和脉冲法测试原理，建立声波垂直入射情况下水下材料吸隔声性能测试近场长脉冲传递函数法，10mm均匀钢板模型声学性能试验表明，压力环境下钢板反射及隔声性能测试值与理论值基本一致，反射系数测试偏差小于0.1，隔声量测试偏差小于1dB，可以采用近场长脉冲传递函数法测量声波垂直入射情况下材料声学性能，可有效克服边界反射对测试的影响。

Measurement of absorption coefficient and transmitting loss on underwater materials using the long pulse transfer function method

In order to eliminate influence of wall sound reflection in acoustic performance test of underwater materials, the long pulse transfer function method is established to measure the absorption coefficient and transmitting loss of underwater materials at vertical incidence by transfer function method and pulse method. The measurement of the steel plate acoustic performance shows that the measurement value of the reflection coefficient and transmitting loss of steel plate is agreed on that of theoretical value at pressure environment. The difference of reflection coefficient between measurement value and theoretical value is less than 0.1, and that of transmitting loss is less than 1dB. The long pulse transfer function method may be used to measure the acoustic performance test of underwater materials, and eliminate effervescently influence of wall sound reflection.