大流量自吸离心泵机组轴与曲轴的模态分析

为研究大流量自吸离心泵机组轴与曲轴的振动特性,基于ANSYS有限元分析软件对大流量自吸离心泵机组轴与曲轴的模态特性进行研究,分析了大流量自吸离心泵机组轴与曲轴前5阶振型图及固有频率,并对其各阶固有频率对应的临界转速进行研究.研究表明,大流量自吸离心泵机组轴在支撑间距以及形式的影响下,主要体现出扭曲振动,且第4阶发生了2次扭转变形,呈现对称变化分布.与此同时,大流量自吸离心泵机组轴的设计转速为2 200.00 r/min,而大流量自吸离心泵机组轴的最低临界转速达到2 848.07 r/min,高于实际转速2 200.00 r/min,从而避免了发生共振的可能.采用合理的结构设计可以有效地避免大流量自吸离心泵机组轴与曲轴发生共振,通过模态分析得到振型图和动画显示,清晰地展现出大流量自吸离心泵机组轴与曲轴的动态特性,为系统的安全运行、振动分析以及结构的优化设计提供重要的理论依据.

Modal analysis of a high flow self-priming centrifugal pump shaft and crank-shaft

To study the vibration characteristics of the high flow self-priming centrifugal pump shaft and crank-shaft, based on ANSYS finite element analysis software. The high flow self-priming centrifugal pump shaft and crank-shaft modal characteristics were studied, the shaft and crank-shaft front 5-order vibration mode and natural frequency diagram of the high flow self-priming centrifugal pump were analyzed, and its natural frequency corresponding to the critical speed was studied. It is found that a high flow self-priming centrifugal pump shaft in the support spacing and forms mainly reflects the twisted vibration, and the fourth-order torsional deformation occurs two times, showing the symmetrical distribution change. At the same time, the design speed of the high flow of self-priming centrifugal pump shaft is 2 200 r/min, while the minimum critical speed of the high flow self-priming centrifugal pump shaft is 2 848.07 r/min, far higher than the actual speed of 2 200.00 r/min, thereby avoiding the possibility of resonance.The results show that the reasonable structure design can effectively avoid the high flow self-priming centrifugal pump shaft and crank-shaft resonance. Vibration mode diagrams and animation obtained by modal analysis, clearly show the dynamic characteristics of the high flow self-priming centrifugal pump shaft and crank-shaft, which provides an important theoretical basis for the safe operation of the system, vibration analysis and optimization design of the structure.