Research on the Pump Shaft Stability Analysis of Multistage Centrifugal Pump During Closed-Valve Start-Up Process

Yun Long,Jie Fang,Qiang Fu,Bin Lin,Rongsheng Zhu,Longbo Xu,Jie Ge

doi:10.3389/fenrg.2020.00186

Abstract

In order to analyze the pump shaft stability of multistage centrifugal pump during the closed-valve start-up process, the transient internal fluid field and structural field during the closed-valve start-up process of the TDM 35-140×13 segmental multistage centrifugal pump are solved by transient fluid-solid coupling. The transient deformation and vibration velocity of the pump shaft are analyzed. It is found that the maximum deformation amount of the third stage impeller and the pump shaft cylindrical contact surface (N=7 node area) during the whole closed-valve transition start-up process is the largest. The maximum deformation in the region where the nodes 1≤N≤10 are significantly greater than that in other regions. In the 11≤N≤19 node, with the node position coordinate value N increasing, the maximum deformation amount is continuously decreasing. During the entire closed-valve transition start-up process, the vibration speed of the pump shaft fluctuates drastically. In the node of 1≤N≤19, with the node position coordinate value N increasing, the maximum vibration velocity first increases and then decreases. The maximum vibration speed at N=11 nodes is higher than that of all other nodes.

Highlights

During the frequent start-up process of multistage centrifugal pump, the structural part in contact with the internal fluid will be affected by the changing fluid pressure
The constraint direction of the bearing surface on the inlet side of the impeller is set During the centrifugal pump of the closed-valve start-up process, the radial force of the impeller is in a state of sharp change due to fluid acceleration and rotation
The transient internal fluid field and the structure field of the multistage centrifugal pump are solved by transient fluid-solid coupling and the transient deformation and vibration velocity of the pump shaft are analyzed

Summary

INTRODUCTION

During the frequent start-up process of multistage centrifugal pump, the structural part in contact with the internal fluid will be affected by the changing fluid pressure. The constraint direction of the bearing surface on the inlet side of the impeller is set During the centrifugal pump of the closed-valve start-up process, the radial force of the impeller is in a state of sharp change due to fluid acceleration and rotation. It can be seen from the Figure 7.

Findings

DISCUSSION

CONCLUSION