毕业论文移动版

摘要随着全球经济的快速发展，国际物流需求量不断增大。海运作为最重要的国际物流运输手段，对海上运输工具——船舶的需求量不断增大。与此同时，随着人们生活水平的不断提高，对高速船舶、豪华游轮等快速性、娱乐性船舶的需求量也不断增加。船舶在航行过程中，全船各种机械设备如主机、螺旋桨以及一系列的工作设备在工作中不断向外辐射噪声能量，产生严重的噪声污染，对船员的身体、生活、休息和工作造成非常不利的影响；其次，噪声产生的辐射越强，产生的影响就越严重，例如对一些仪器产生很大的影响。第一，误差较大，第二,工作精度降低，第三，使用寿命缩短等。因此，船舶设计时，有必要在船舶设计之初对全船的舱室声学降噪优化进行顶层设计，降低船舶降噪的成本，减轻船舶重量，具有重要的意义。78140

本文围绕一艘散货船舶，基于统计能量法基本原理，利用VA one软件建立了全船的SEA模型，加载主机的噪声能量激励，计算得出上层建筑各舱室噪声声压级以及各层甲板的振动速度级，研究主机噪声的能量通过辐射，传递等方式，对上层甲板的而产生影响。通过研究全船噪声能量分布以及噪声能量传递路径分析，并在此基础上，对全船进行一系列的噪声控制手段，如主机的隔振处理、阻尼减振处理、舱室的吸音敷料处理等措施，舱室噪声值得到了大幅度地降低。

毕业论文关键词:统计能量；噪声预报；VA one；优化

Abstract With rapid development of global economy, the quantity demand of international logistics is increasing。 And sea transportation is the most important means of international logistics transportation。 Hence, the demand of ship, which is main sea transportation tools, is unceasingly increasing。 At the same time, with the improvement of living standards,the demand of the rapid shape and recreational ship, such as high-speed craft and cruise ship,is also increasing。 During navigating, noise energy willradiate outward from various machines such as the main engine and propeller as well as a series of working equipments, which will do harm to mariners'health and effect their orthobiosis。 What's more, the noise radiation more strong, the influence resulting from it more serious。 Forqexample, the noise radiation has a strong impact on some instruments。 First, there will be significant errors in data measured by these instruments。 Second, there will be deterioration in working accuracy of these instruments。 Third, the service life of these instruments will be reduced。 Therefore, it is necessary and meaningful to create top-level design for cabin acoustic noise reduction optimization from the very beginning of design process, reduce the cost of anti noise onboard and reduce the weight of ship。

Taking a bulk coal ship as research objective, the research in this paper bases on principle of statistical analysis and utilizes software of VA one to build a SEA model of the whole ship。 First, the research loads noise excitation and works out every cabin of superstructure'sound pressure level and all decks' vibration velocity level。 Then the research studies how the energy of main engine transmitted by radiation and delivery impacts the upper deck。 Thirdly, basing on the study of whole ship's nois energy distribution and analysis of noise energy's transfer path, this research makes noise control of the whole ship by means of vibration isolation for the main engine, damping vibration attenuation and sound absorption covering so that the cabin noise is reduced significantly。

Keywords: Statistical energy; noise prediction; VA one; optimization

目录

第一章 绪论 1

1。1研究背景 (责任编辑：qin)