文档介绍：摘 要
随着科学技术的发展,船用齿轮箱作为船舶动力传动系统中十分重要的部件, 正朝着大功率、高转速、低噪声方向发展。目前,我国齿轮装置设计水平与国际先进水平相比还存在较大差距,特别表现在高速重载齿轮传动,减振降噪问题已成为制约我国高性能船用齿轮箱研制的瓶颈。因此,开展高速重载船用齿轮箱减振降噪技术研究,具有重要理论意义和工程应用价值。
论文课题来源于国家自然科学基金资助项目,综合运用多体系统动力学、非线性振动理论以及声-结构耦合方法,对船用齿轮箱进行辐射噪声预估及声-结构灵敏度分析。本文的主要研究工作如下:
①在 LMS 软件的 Motion 模块中,建立船用齿轮箱多刚体动力学模型,考虑齿轮时变啮合刚度、阻尼、侧隙以及轴承刚度、阻尼等非线性因素, 采用变步长向后差分法(BDF)对齿轮箱进行刚体动力学分析,得到各级齿轮副动态啮合力及轴承支反力。
②对船用齿轮箱进行柔性化处理,建立齿轮箱动态响应分析模型,通过模态分析得到齿轮箱固有频率及振型;运用模态叠加法对齿轮系统进行动态响应分析, 得出齿轮箱箱体表面节点的振动位移、振动速度及振动加速度。
③建立包含船用齿轮箱结构网格、声学网格、场点网格的声振耦合分析模型, 以齿轮箱轴承处的支反力为声振耦合模型的边界条件,采用声学有限元法对齿轮箱进行辐射噪声预估,得到箱体表面及场点的声压。
④以船用齿轮箱箱体壁厚和材料弹性模量为结构参量,以齿轮箱外声场场点声压为声学参量,构建船用齿轮箱声-结构灵敏度分析模型,综合运用 Nastran 和 LMS 等软件,求得对场点声压影响较大的结构参量,为齿轮箱声学优化设计变量的合理选择提供依据。
关键词:船用齿轮箱,多体动力学,声振耦合,辐射噪声,声-结构灵敏度
ABSTRACT
The marine gearbox is an important transmission part of ships, which hankering high power, high speed and low noise with the development of science and technology. Presently, a big gap between China and foreign advanced level in designing gear device still exists. Especially in the field of high speed and heavy load gear transmission, vibration and noise reduction has e a bottleneck which restricts the development of high-performance marine gearbox in China. Therefore, the research on vibration and noise reduction of the marine gearbox can bring important theory significance and great engineering values.
The topic of this paper is supported by National Natural Science Foundation of China. Using the theories of multi-body dynamics, nonlinear vibration and acoustic-structure coupling prehensively, the prediction of radiated noise and analysis of acoustic-structure sensitivity of the marine gearbox are carried out. The
main research work in this paper can be summarized as follows:
The multi-body dynamics analysis model of the marine gearbox is established in the software of LMS . Taking the time-varying mesh stiffness,
mesh damping, tooth backlash, bearing stiffness and damping into considerat