Research On Vibration And Noise Source Separation And Quantification Of Submarine Cabin Model

Acoustic stealth performance is an important indicator to measure the submarine combatcapability. In low-speed cruising, the main vibration and noise sources of the submarine is themechanical structure-borne noise, the control and reduction of the mechanical structure-bornenoise is the first link to be taken into account in the acoustic design of the submarine.Mechanical structure-borne noise is generated by the vibration of the internal mechanicalstructure of the submarine, and it was transferred to the shell of the submarine through thestructure inside the submarine, and it radiates to the far-field to form the radiated noise. Thesubmarine has a large number of vibration and noise sources, the serious coupling problemamong them and the complexity of vibration transmission path, leading that the separationand quantification of its vibration and noise source is a very difficult task. For proceeding thetargeted noise control, it’s essential to carry out the research of vibration and noise sourceseparation and quantification for determining the contribution of various types of vibrationand noise sources.Since the physical processes of the internal electromechanical equipment vibrationexciting the shell vibration to arise the formation of radiated noise is modeled, thecombination of the coherent analysis, the multiple coherent analysis and the partial coherenceanalysis are applied to analyze the vibration transfer path of the electrical and mechanicalequipment inside the submarine. The information processing method of recognizing thevibration transfer path is established which can achieve the isolation of the vibration transferpath in order to achieve the purpose of reducing the mechanical structural-borne noise. Basedon the coherence analysis and the partial coherence analysis, vibration and noise source of thesubmarine cabin model are separated and quantified to provide references for the acousticdesign of the submarine.Based on the information similarity the method of vibration transfer path analysis isproposed. The input points which have major contribution to the output points are selected bythe coherent analysis. The completeness of the input points is verified by computing themultiple coherences of the input points. If the input points are mutually coherent, the partialcoherence analysis is used to complete the identification of the vibration transfer path. Thesimulation study of transfer path analysis is carried out under the condition of the input pointsare mutually independent or coherent, and the effectiveness of the method is verified. Themethod of feature extraction is researched for the vibration signal of submarine electromechanical equipment. The vibration signal is analyzed from different domains.Hierarchy diagnosis method are employed to the vibration and noise source of submarinecabin model based on the combination of the coherence analysis, the partial coherenceanalysis and analytic hierarchy process, so as to achieve the purpose of vibration and noisesources separation and quantization. The simulation of hierarchy diagnosis proves that thehierarchy diagnosis method can be applied to solve the separation and quantification of thevibration and noise source problem.On the submarine cabin model test platform, the experimental study of vibration transferpath analysis and the separation and quantification of vibration and noise source areproceeded. Based on the information similarity, the information processing method of transferpath analysis are applied to analyze the transfer path of the internal electromechanicalequipment vibration, it transfers to the shell of the submarine cabin model and radiates to thefar-field to form the radiated noise. Based on hierarchy diagnosis, the diagnostic model of thevibration and noise source separation and quantification are established to separate andquantify the vibration and noise source. The results of experimental data processing areverified by the segment operation method. According to the analytic result, by comparisonwith the hierarchy diagnosis based on the coherence analysis, the hierarchy diagnosis basedon the partial coherence analysis has superior position under the condition of the input pointsare mutually coherent.