| With the development of ships in the direction of large-scale,rapid,and heavy-loading,the crew seems to have higher and higher requirements on their living conditions and their own health,which requires ship designers to optimize the comfort of ship cabins.For people who work at sea for a long time,the quality of the working environment mainly depends on the noise level of the working space.Therefore,preventing the crew from being exposed to harmful noise for a long time is one of the important research direction of ship acoustic design.With the release of the new noise standard imposed by the International Maritime Organization（IMO）on July 1,2014,the acoustic design of ship cabins has become a focus of current research.The research work of thesis is mainly carried out from two aspects: one of is the theory method of cabin noise prediction,and the other is about the optimization design of cabin layout and the control measures.Through the analysis of theoretical methods,simulation calculation and evaluation based on real ships,acoustic design of cabin layout optimization,and research on sound insulation and vibration isolation technology,the aim is to improve the accuracy of cabin noise prediction and reduce the impact of cabin comfort.The main research contents are as follows:In terms of forecast methods,the traditional methods are sorted out,and combined with the advantages of the empirical formula and the statistical energy method,the parameters calculated by the empirical formula method are used as the input of statistical energy analysis method,and the forecast method is applied to the actual ship calculation.Taking a survey vessel as the research object,the statistical energy model is established,and according to the empirical formula to estimate the strength of the ship’s main excitation sources,and then select them as the model input of its statistical energy analysis model.Choosing some important goal cabin forecast analysis as the research object,and comparing the forecast results value with the corresponding standard.The comparison of the results shows that the mixing method is faster and more accurate than the traditional method.In terms of cabin layout optimization and control measures,through the establishment of cabin layout optimization model,based on the Hungarian method,considering the energy transfer relationship between cabins,the optimal cabin layout plan is solved,and the calculation verification is performed in conjunction with the actual model.The results showed that the optimized cabin layout can make the noise of cabin achieve better effect,saving the cost of the noise reduction.Finally,the target cabin that has not reached the standard is taken as the research object.By analyzing the energy input of the target cabin,the plate structure that contributes the most energy to the cabin is found,and corresponding noise reduction measures are taken to compare and analyze the results before and after.The results show that under the condition that the intensity of the noise source is constant,the cabin can reach the noise standard faster after reasonable layout and optimization measures.The prediction methods and optimization measures proposed of this thesis have certain reference value for the subsequent acoustic design of ship cabins and optimization of cabin noise reduction. |
