The Investigation on Cabin Noise Control of Ship Structure Based on SEA Graph Method

The noise of ship structure is mainly transmitted by two types which are air sound and structural sound. As a kind of mechanical energy, sound is produced by the sound source and goes through various transmission paths to the recipient. This process is a process of constant loss of energy. Therefore, according to aspects of noise generation, output, transmission and reception, the principle of cabin noise control can be divided into four aspects which are cabin structure acoustics design, noise source control, noise transfer path and individual protection at the end of cabin. In order to determine the best noise reduction measures, noise control measures should be considered on the basis of three principles of science, advanced nature and economy. Statistical energy analysis (SEA) graph method is compared a series of adjacent loss factor matrices in the SEA model with the data structure of graphs in graph theory, a plurality of transmission path of SEA model can be obtained by giving different weights to adjacent matrix loss factor matrices in SEA model. The problem of finding maximum energy transfer path in the SEA model is actually equivalent to the issue of seeking shortest path in the graph theory. In order to reduce the cabin noise of the ship structure, it is necessary to know the main source and the main energy conduction path of the noise cabin. The problem is translated into K shortest path problem in graph theory. In this paper, acoustical sensitivity analysis of noise reduction design parameter is developed according to sound energy transmission of two layer cavities structure, which can guide the noise reduction design of the ship cabin. The proposed cabin noise control method is applied to the problem of overproof cabin noise, and the optimal noise control scheme is obtained.