Author(s): Lei Wang; Shuang Yu; Linmin Shang; Jingwei Cao; Zhengwei Wang; Xiaobing Liu

Linked Author(s):

Keywords: Variable speed pump-turbine; Axial hydraulic thrust; Numerical simulation; Radial force

Abstract: When the pump turbine does variable speed operation, it can improve the operation efficiency in the turbine mode, and it can improve the automatic frequency adjustment efficiency in the pump mode. However, the hydraulic thrust will also change when the speed changes, and the magnitude of the hydraulic thrust is crucial for the safe and stable operation of the unit. The work of this paper is to analyze the changes of the axial hydraulic force and radial force with the change of the speed by numerical simulation method. It is found that the fluctuation of axial hydraulic thrust can reach about 34 t at 398.57 rpm speed, 37 t at 412.16 rpm speed and 21 t at 428.6 rpm speed. The fluctuation of radial force can reach about 13.78 t, 14.4 t and 12.4 t. The purpose of this paper is to use the simulation results to understand the hydraulic thrust characteristics and ensure the stability of the unit to select the appropriate speed range, provide the basis for stable operation of the unit under design conditions.

DOI: https://doi.org/10.1088/1742-6596/2752/1/012052

Year: 2023