The load criteria for ship mechanical noise prediction in low frequencies and experimental validation  

作　　者：Xi-An Liu De-Qing Yang Qing Li 

机构地区：[1]State Key Laboratory of Ocean Engineering,School of Naval Architecture,Ocean and Civil Engineering,Shanghai Jiao Tong University,Shanghai 200240,China

出　　处：《Journal of Ocean Engineering and Science》2023年第3期278-293,共16页海洋工程与科学（英文）

摘　　要：The loading method of the external excitations generated by the equipment directly affects the predicted result of the mechanical noise which should be the same under different excitation forms for the given equipment.In this paper,general load criteria are proposed to define forces/moments as the standard form and convert other forms of loads in the low-frequency domain.As the most typical form to charac-terize equipment excitation,acceleration load loading methods for different conditions are investigated.The equivalent formula between ideal accelerations and generalized forces establishes the first load cri-terion.The second load criterion is proposed to address the issue of an average acceleration loading,in which the phase and amplitude distribution are both absent,and cannot apply to the load identification.The upper and lower limits of the mechanical noise can be determined by the vibroacoustic transfer func-tion of the three load models,and the energy-averaged value is used to represent the mechanical noise.Furthermore,the third criterion is used to handle the case where the acceleration load is given by the results of a bench test.According to the equipment source descriptor invariance,the conversion method is achieved between the bench test and the real ship based on the transfer function of a load model,and the mechanical noise is predicted by an equivalent energy method.Finally,a three-parameter method to quantitatively evaluate the well-fitting of experimental and numerical results,and the load criteria are well validated by underwater acoustic experiments of an experimental model.

关 键 词：Ships’mechanical noise Load criteria Vibroacoustic transfer functions Underwater acoustic experiments Accelerations load Three-parameter method 

分 类 号：O17[理学—数学]