摘 要随着船舶行业的不断发展,船舶设备所导致的噪声问题日益严重,舰船振动噪声的问题受到越来越多的关注。为此,本文基于统计能量分析法来研究舰船舱室的噪声预报和控制的方法,并且对船舶结构声学性能的优化提供一些指导建议。本文首先介绍了统计能量分析法(SEA)的基本原理以及前提条件,接着详细介绍了SEA法的基本参数(模态密度、内损耗因子和耦合损耗因子)的确定。然后结合某典型内河船,基于统计能量分析法,采用VA one软件使用板、梁、声腔和半无限流场等单元建立船舶舱室的 SEA 模型,考虑主机噪声源的激励作用,分析各个舱室的噪声水平,进而研究对船舶舱室噪声的控制方法。本文通过控制变量的方法,主要仿真模拟出船板材料的种类和厚度对船舶舱室噪声振动的影响,并进行了分析,选择出相对合理的结构材料。最后通过在主要舱室内部铺设不同吸声材料和阻尼材料的方法,对船舶舱室进行降噪处理,并分析其降低噪声效果,进而找出比较有效的减振降噪的方法。87025
毕业论文关键字:统计能量分析法,VA one,噪声预报,噪声控制
Abstract With the continuous development of shipping industry, the noise caused by ship equipment becomes more and more serious。 More and more attention has been paid to the problem of vibration and noise of ships。 Therefore, this paper studies the prediction and control of the noise based on the statistical energy analysis, and provides some suggestions for the optimization of the acoustic performance of the ship structure。 This paper mainly studies the basic principle of statistical energy analysis (SEA) and the preconditions, and then introduces the basic parameters(modal density, internal loss factor and coupling loss factor) of the SEA。 Based on the SEA, and according to a typical inland waterway ship, a SEA model is built by shell, beam, acoustic cavity, semi-infinite field and soon。 And then, calculating the noise level of each cabin by considering the excitation of main engine and studying the control method of cabin’s noise。 Through the method of control variables, the paper analyses the main effect of the type and thickness of plate material on the noise and vibration of ship cabin, and selects a reasonable noise reduction material。 Finally through laying method of different absorption and damping material in the main cabin, the paper analyzes the effect of reducing noise and finds out the effective method of reducing vibration and noise。
Keywords:Statistical Energy Analysis,VA one,Noise production,Noise control。
目 录
第一章 绪论 1
1。1 本课题的研究背景及意义 1
1。2 国内外舰船舱室噪声的研究进展综述 1
1。2。1 经验预测法 1
1。2。2 有限元结合边界元法 2
1。2。3 统计能量分析法(SEA) 2
1。3 本课题的研究内容和研究方法 3
第二章 统计能量分析的基本原理 4
2。1 基本含义 4
2。2 统计能量分析法的适用范围 4
2。3 子系统之间的功率流平衡关系式 5
2。3。1 子系统的确定 5
2。3。2 子系统间的纯功率流