带弹性环式挤压油膜阻尼器转子系统装配特性及试验研究

Assembly Characteristics and Experimental Study of Rotor System with Elastic Ring Squeeze Film Damper

弹性环式挤压油膜阻尼器(Elastic ring squeeze film damper,ERSFD)作为航空发动机中典型的稳定和振动控制结构,其装配特性(配合紧度)在一定程度上影响组合支承系统的刚度和阻尼,进而影响转子系统的动态特性,但相关研究尚少。为了研究配合紧度对ERSFD动态参数特性的影响,建立了考虑配合紧度的ERSFD耦合模型。采用短轴承理论,分析了配合紧度对弹性环变形、ERSFD油膜压力、油膜厚度和承载力的影响。然后,建立了考虑ERSFD配合紧度的组合支承转子有限元模型,探究配合紧度对转子系统动态特性的影响。结果表明,过盈配合将导致ERSFD转子系统临界转速升高,但ERSFD的减振效果不明显;间隙配合下ERSFD转子系统的临界转速降低,减振效果明显。最后,搭建了ERSFD转子试验台,通过数值仿真与试验结果对比,验证了部分仿真结果的正确性。

As the typical stability and vibration control structure in aero-engine,the assembly features(fit tightness)of elastic ring squeeze film damper have a certain effect on the stiffness and damping of the combined support system,and then affects the dynamic characteristics of the rotor system,but there are few relevant researches.In order to study the effect of fit tightness on the dynamic parameter characteristics of ERSFD,an ERSFD coupling model considering fit tightness was established.Using short bearing theory,the influence of fit tightness on elastic ring deformation,ERSFD oil film pressure,oil film thickness and bearing capacity was analyzed.Then,the finite element model of the combined supporting rotor is established considering the ERSFD fit tightness,and the influence of fit tightness on the dynamic characteristics of the rotor system was investigated.The results show that interference fit will increase the critical speed of ERSFD rotor system,but the damping effect of ERSFD is not obvious.The critical speed of ERSFD rotor system decreases with clearance fit,and the effect of vibration reduction is obvious.Finally,the ERSFD rotor test bench is built,and the correctness of the simulation results is verified by comparing the numerical simulation and experimental results.