【作者】 刘敏；

【导师】 郎济才；

【作者基本信息】 哈尔滨工程大学 ， 船舶与海洋结构物设计制造， 2009， 硕士

【摘要】 结构振动及其辐射噪声之间的相关特性被一些学者所研究,在众多的科学及工程领域中,振动与辐射噪声也是人们所关心的话题。本文的主要内容是应用实验和理论近似计算的方法,研究双层圆柱壳结构振动与辐射噪声之间的相关特性,用振动的量来表示噪声,已达到通过控制振动来控制噪声的目的。首先,研究双层圆柱壳结构振动及声辐射的理论,对其研究方法进行总结和分析,以实验及实测数据为依据,确定本文的研究方法和出发点。其次,应用谱分析的方法,计算各工况下的自功率谱,确定模型的共振频率。计算单频激振振动级、近场声压及白噪声激振的周向加速度,分析各工况的振动特性,确定研究工况。第三,应用关联系数的方法编制MATLAB程序,计算确定工况下单频激振时振动与辐射噪声的关联度,分析单频激振时模型各点振动与辐射噪声的关联特性。第四,应用灰色理论非等间隔GM(1,1)模型,建立双层壳结构振动与辐射噪声的数学模型,计算外壳相应角度测点振动在水听器处的关联振动值。之后,建立关联振动对辐射噪声的数学模型,计算不同激振频率下的辐射噪声,并与实测数据进行比较,分析其误差,验证经验公式的正确性,分析振动与其辐射噪声的相关特性。更多还原

【Abstract】 The relevant characteristic of structure vibration and sound radiation is researched on by some scholars and is paid attention to people in many fields of science and engineering. The main content of this thesis is that through the method of experimentation and theory approximately calculation, researching on the relevant characteristic of structure vibration and sound radiation of double cylindrical shell, using the vibration to denote the radiation sound in order to control the radiation sound by controlling the vibration.Firstly, the theory of vibration and sound radiation of double cylindrical shell are introduced, the method is researched and analyzed in this thesis. The method in this thesis is confirmed basic on the experiment and measured data.Secondly, the self-power spectrum of different behaviors is calculated in this thesis with the spectrum analysis method and the resonance frequency of the model is confirmed. The vibration level and near field sound pressure under the condition of single-frequency shock excitation and the girth acceleration under the condition of flat noise shock excitation are calculated in this thesis. Through the calculating the vibration characteristics of different behaviors are analyzed and the researched behavior is confirmed.Thirdly, basic on the method of relevancy coefficient, the MATLAB computation programs are established to calculate the relevancy degree of the vibration and sound radiation under the confirmed behavior with single-frequency shock excitation. The relevant characteristic of vibration and sound radiation of the mode is analyzed.Fourthly, basic on the gray theories model of GM (1,1), the math’s model of vibration and sound radiation of double cylindrical shell is established. The model is used to calculate the shell relevancy vibration at the hydrophone. Then the calculation model of relevancy vibration to the sound radiation is established and the model is used to calculate the sound radiation at the hydrophone under different shock excitation frequency. The calculated and actual measurement results are contrasted in this thesis and the error between them is analyzed what is used to validate the empirical equation’s correctness. And the relevant characteristic of vibration and sound radiation of double cylindrical shell is analyzed in this thesis.更多还原