螺旋输送器临界转速的数值分析与研究

Numerical Analysis and Research on Screw Conveyor Critical Speed

为了避免螺旋输送器转子系统生共振需计算其临界转速。利用ANSYS软件建立螺旋输送器一维有限元模型,考虑了转子系统的陀螺效应,经过多次模态求解绘制了系统Campbell图,进而得到系统的临界转速。通过研究系统在不平衡激励下的响应,得到了共振位移与频率的关系,发现系统的薄弱位置。分析轴承刚度变化对系统临界转速的影响,发现在轴承刚度小于1 GN/m时系统临界转速随轴承刚度降低而降低。结果表明,利用ANSYS软件可以方便的研究转子系统的临界转速,进而提供对卧螺离心机关键位置的监控提供了参考。

To avoid violence running vibration, it is necessary to figure out the critical speed of screw conveyor and to keep it be far away from the critical speed. The finite element model of screw conveyorrotor system of screw conveyor is established with considering gyroscopic effect based on ansys. By calculating it＇s natural frequency and mode of vibration system, CAMPBELL chart is drew. With the CAMPBELL chart the critical speed is known. Then the resonance problem of the rotor may produce after unbalance excitation was researched with the relationship diagram between resonance displacement and frequency. The regularity about the main support stiffness working on rotor critical speed is investigate, the analysis results show that when the main support stiffness is less than 1 GN/m, the rotor＇s critical speed increase obviously with the main support stiffness increasing. The results show that ANSYS provides a effective way to calculate a rotor system＇s critical speed and monitor the screw conveyor.