混响水池测量方法及应用

Reverberation pool measurement method and its application

针对混响水池不满足扩散场条件,理想混响室理论无法应用这一问题开展了混响水池测量方法研究。本文基于简正波理论,推导了水下封闭空间中混响控制区空间平均声压与声源辐射声功率之间的关系,建立了混响水池测量方法理论基础,不再要求混响水池声场满足扩散场条件;基于标准声源分别采用自由场法及混响水池法测量其辐射声功率,以对混响水池测量方法的准确性进行验证;最后,采用混响水池法分别测量了水下声源辐射声功率、管路噪声、材料吸声系数的测量并进行及水听器的校准。理论及试验研究结果表明:在水池的截止频率以上,基于混响水池法可以较准确地测量水下声源的辐射声功率,采用该方法测得的水下推进器电机的辐射声功率与海上包面法的测量结果相差不超过2 dB;混响水池测量方法可解决水下声源辐射声功率、管路噪声、材料吸声系数的测量及水听器的校准问题。

The measurement method for a reverberation pool is investigated,taking account of the facts that the reverberation pool does not satisfy the conditions for existence of a diffuse field and that the theory applicable to an ideal reverberation room in the air cannot be used for a reverberation pool.Based on normal wave theory,a relationship is derived between the spatial average sound pressure level in the reverberation control area far from the source and the sound source radiated power level,and the theoretical basis for the measurement method of a reverberation pool is established and the reverberation pool sound field is no longer required to meet the diffusion field conditions.The standard sound source is taken to measure the radiated sound power by the free field method and the reverberation pool method respectively to verify the accuracy of the reverberation pool measurement method.Finally,the reverberation pool method is used to measure the radiated sound power of underwater sound sources,pipeline noise,material absorption coefficient and calibrate hydrophones.Both the theoretical and experimental results show that above the cutoff frequency of the reverberation pool,the radiated sound power of an underwater sound source can be measured accurately using the reverberation pool method.The radiated sound power from a marine propulsion motor by this method differs from that obtained using the enveloping surface method by no more than 2 dB.The reverberation method can be used for measuring the radiated sound power of underwater sound sources,pipeline noise,diffuse sound absorption coefficient of underwater material and calibrate the hydrophones.