基于有限元素法的挤压油膜动力特性研究

挤压油膜阻尼器(SFD,Squeeze Film Dumpers)因减振效果显著,目前广泛应用于航空发动机等高速旋转机械中.在基于雷诺方程的短轴承近似解或长轴承近似解基础上,提出了求解带挤压油膜阻尼器的转子支承系统稳态动力特性的有限元挤压油膜计算方法,该方法能有效地模拟转子系统在各种工作条件下的油膜力模型.为了验证上述理论分析结果,用有限元法计算了带挤压油膜阻尼器转子系统的油膜压力分布和油膜阻尼,分析中还考虑了油膜惯性力的影响.通过对某发动机转子支承系统的模拟计算,并与试验结果进行对比分析,证明给出的系统动力特性计算方法及性能分析结果可用于工程实际. 

Dynamic characteristic of squeeze film based on finite element method

SFD(squeeze film dampers) designed to provide proper amounts of damping and stiffness to alleviate the problem of vibration are used extensively in almost all high-speed rotating machines, such as aeroengine. A squeeze film analysis based on finite element method was proposed for solving the steady state dynamic characteristic of the rotor system supported on squeeze film damper and elastic supports, but most closed form solutions of Reynolds’ equation assumed either a short bearing approximation or a long bearing approximation generally. The finite element model of damper was simulated by the variation of geometry within the flow path. In order to validate the results of theoretic analysis, the pressure distribution and equivalent film damping of typical SFD were calculated by using the finite element method. The effects of film inertia forces were also calculated. Comparison of calculational and experimental results show that the analysis and calculation methods and results of the rotor system dynamic characteristic can be used in engineering practice.