摘要
支座松动转子因两端刚度不对称而引发振动异常增大,进而可能导致转子出现裂纹故障,裂纹和松动故障耦合下的转子系统呈现强非线性特性.建立滚动轴承支承的支座松动-弓形裂纹转子动力学模型,研究转速、松动间隙、松动质量及裂纹角等对转子系统非线性动力学响应的影响.考虑非线性Hertz接触力,采用分段线性方程描述支座松动的刚度和阻尼,转子横向裂纹采用呼吸裂纹模型来研究,依据拉格朗日方程建立转子系统动力学方程,采用Runge-Kutta法求解方程获得转子振动响应的分岔图、频谱图、轴心轨迹图、Poincaré图等.计算结果表明,当系统转速达到2300rad/s时,松动-裂纹耦合故障系统较仅裂纹系统在1/3分频处有明显的间谐波成分,混沌区域更为宽泛;当裂纹参数恒定时系统随着松动间隙减小会更加稳定;当松动质量m_(s)>41.25kg时,系统振幅剧增,发生“跳跃”现象.研究工作对松动-裂纹转子系统的故障诊断和健康监测具有重要的工程应用价值.
The vibration of the rotor with the loose support increases abnormally due to the asymmetry of the stiffness at both ends,which may lead to the crack fault of the rotor.The rotor system under the coupling of the crack and the loose faults shows the strong nonlinear characteristics.The dynamic model of the rotor with the pedestal looseness-crack,supported by the rolling bearing is developed,and the effect of the rotational speed,the loose clearance,the loose mass and the crack angle on the nonlinear dynamic response of the rotor system is studied.Considering the nonlinear Hertz contact force,the breathing crack model is applied in this study and the piecewise linear equation is used to describe the stiffness and damping of the loose pedestal.The dynamic equation for the rotor system is formulated by using the Lagrange equation.The equation is solved using the Runge-Kutta method to get the bifurcation diagram,the spectrum diagram,the axis trajectory diagram,and the Poincarédiagram of vibration response for the rotor system.The research results show that when the rotating speed increases up to 2300rad/s,the looseness-crack coupling fault system has obvious interharmonic components at 1/3 frequency division and the chaotic region is wider compared with that of only crack rotor system.When the crack parameters are constant,the system will be more stable with the decrease of the loosening gap.When the loosening mass ms is greater than 41.25 kg,the amplitude of the system increases sharply,and the jumping phenomenon occurs.The research work has important engineering application value for the fault diagnosis and the health monitoring of the looseness-crack rotor system.
作者
李姚
南国防
丘学文
姚夏
Li Yao;Nan Guofang;Qiu Xuewen;Yao Xia(School of Energy and Power Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China)
出处
《动力学与控制学报》
2024年第3期62-70,共9页
Journal of Dynamics and Control
基金
国家自然科学基金资助项目(52275118)。
关键词
转子
滚动轴承
裂纹
松动
耦合故障
rotor
rolling bearing
crack
looseness
coupling fault
