轮盘搭接干摩擦接触结构转子减振特性研究

Damping characteristics of a dry-friction contact rotor with an overlapped wheel

轮盘搭接干摩擦接触结构转子广泛应用于航空发动机、燃气轮机等机械中,搭接结构在旋转时系统的振动响应发生变化,会影响设备的正常运转,因此有必要对搭接摩擦结构转子的振动特性进行研究。考虑到搭接结构的接触面的干摩擦特性,采用带有迟滞特性的宏观滑移模型模拟搭接结构的接触面摩擦,将转子工作时搭接结构接触面的非线性摩擦力转化为等效刚度和等效阻尼的影响。搭建搭接转子试验台,并与非搭接结构转子和螺栓连接结构转子进行对比,试验结果表明:当轮盘搭接结构转子旋转时,搭接接触面出现相对滑移,通过摩擦耗散振动能量,从而达到减振效果;螺栓连接结构和搭接结构均可降低转子振动加速度的最大值,且轮盘搭接结构转子的减振效果优于螺栓连接结构转子;增加搭接间隙会导致振动位移增大。

Rotor wheel lap dry friction contact structure are widely used in aero engines,gas turbines and other machinery.The vibration response of the system changes under rotation of the lap structure,which affects the normal operation of the equipment.Therefore,it is necessary to study the vibration characteristics of a rotor with a lap friction structure.Considering the dry friction characteristics of the contact surfaces of the lap structure,a macroscopic slip model with hysteresis was used to simulate the friction between the contact surfaces of the lap structure.The nonlinear friction between the contact surfaces of the lap structure during rotor operation was transformed into the effects of equivalent stiffness and equivalent damping.A lap rotor test platform was built and compared with a rotor with a non-lap structure and a rotor with a bolted connection structure.The test results show that when the rotor with a wheel lap structure rotates,the lap contact surface slips relative to the rotor,and the vibration energy is dissipated through friction,resulting in a reduction in vibration.Both the bolted structure and the lap structure can reduce the maximum vibration acceleration of the rotor,and the vibration reduction effect of the wheel lap structure is better than that of the bolted structure.Furthermore,an increase in lap clearance leads to an increase in vibration displacement.