基于弹塑性理论对具有粗糙表面的长方微元体进行有限元接触分析,根据受力和变形关系得到不同载荷作用下的法向和切向界面接触刚度.将微元体界面接触刚度与宏观结构应力分析结果相结合,给出考虑接触刚度的组合结构动力特性研究方法,分析压气段轮盘接触刚度对某重型燃气轮机拉杆转子固有振动频率的影响.结果表明,界面接触刚度导致转子固有频率降低,随着接触刚度的增加,其对固有频率的影响逐渐减小.接触刚度对转子各阶固有频率的影响不同,法向刚度对第一阶弯曲频率影响较大,切向刚度对第二阶弯曲频率影响较大.%A cuboid finite element contact model with rough surface was analyzed based on elastic-plastic theory,and the normal and tangential interface contact stiffnesses under different loads were obtained according to the relationship between force and deformation. Combining the interface contact stiffnesses of the element with the stress analysis results of a macro structure,a studying method for dynamic characteristics of a composite structure considering contact stiffness was presented. Then,the effects of the contact stiffness of a compressor section on the natural vibrational frequencies of a rod fastening rotor for a certain heavy duty gas turbine were analyzed. The results showed that the interface contact stiffness leads to decrease in the natural frequencies,and its effects decrease gradually with increase in contact stiffness; the effects of contact stiffness on each natural frequency are different,normal contact stiffness has greater effects on the first bending frequency and tangential contact stiffness has greater effects on the second bending frequency.
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