为了使涡轮发动机叶片缘板阻尼结构能起到预期的耗能减振作用,就必须在设计时对各个耗能作用机制有深入了解.鉴于叶片阻尼结构非线性接触因素的存在,在时域内进行接触实时响应分析对计算机能力、耗时和计算的收敛性都带来了巨大挑战.首先在频域内通过理论分析和有限元分析两种方法研究了含非线性接触结构的振动响应分析方法,并基于此方法对某涡轮叶片缘板阻尼结构进行了阻尼效果分析,并对干摩擦阻尼、附加质量和附加刚度三种耗能机制开展了进一步的探索.研究发现叶片阻尼结构除了接触面间的干摩擦耗能外,附加质量和附加刚度也对其产生了明显的耗能作用.且摩擦系数和密度较小时,阻尼效果对其变化较为敏感;阻尼效果与阻尼结构刚度成正比.因此,在阻尼装置结构体积一定的情况下,设计阻尼结构要在保证刚度的基础上,权衡考虑最优密度值和最优摩擦系数,使阻尼效果最好.%An analytical method of vibration response for contact structure with nonlinearity is studied via theoretical analysis and finite element analysis in frequency domain,and the damping effect analysis for damping structure of margin plate of certain turbine blade is carried out based on that method.Then,the farther exploration for energy consumption mechanism of dry-friction damping,added mass and added rigidity is carried out.It is shown that the added mass and added rigidity have obvious energy consumption effect on damping structure besides the dry-friction energy consumption between contact faces,and the damping effect is sensitive to variation of friction coefficient and density when the coefficient and density are small.The damping effect is proportional to the damping structure.Therefore,design of damping structure has to balance optimal density and optimal friction coefficients based on ensuring rigidity under situation of given volume of damping device structure.It makes damping effect better.
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