中文摘要：

为了研究水下工程结构辐射声场的识别问题,基于相位共轭方法采用离散阵元对水下有限长圆柱壳的辐射声场识别进行了数值仿真计算.采用不同的阵列形式分别在近场和远场对圆柱壳表面声压、法向速度、辐射声功率和声强进行了识别及重构误差分析,并讨论了激励频率变化对重构结果的影响.数值计算结果表明：只有在近场采用圆柱形阵列形式并基于声压梯度测量,使用偶极子源才能得到最好的声场重构结果;采用相位共轭方法可以较好地识别结构的表面声压、法向速度、辐射声功率和声强等;在远场使用相位共轭方法仅能够识别出圆柱壳表面声压最大值的位置;激励频率发生变化时该方法仍能得到较精确的重构结果.相位共轭方法具有使用测点少,可自然使用局部重建方法,并且不存在解不稳定问题等优点,具有很好的应用前景.

英文摘要：

The identification and reconstruction of the sound field radiated from a cylindrical shell underwater are studied numerically using discrete elements based on the phase conjugation method for the research of the identification of the radiation of the underwater structure.The surface pressure,the normal velocity,the radiation power,and the intensity of the cylindrical shell are reconstructed by using different array forms in the near and far field.The impact of the changing excitation frequency on the identification of the sound field is also discussed.The results show that the best reconstruction could be achieved by the cylindrical array only made of dipole transceivers based on pressure gradient measurement in the near field and the normal velocity,the radiation power and the intensity could be well reconstructed by the phase conjugation method.For array in the far field only the location of the maximum velocity response and the maximum pressure could be identified.The method can still get the accurate reconstruction results with the change of the excitation frequency.The phase conjugation method for localization and reconstruction of radiation sound field has advantages of using a small number of measurements and no ill-posedness difficulty and is natural to use patch reconstruction method.These features may make the phase conjugation method a powerful noise diagnostic tool.