Hydraulic characteristics and structural stability of the rotor of  a molten-salt pump

Shuang Teng; Can Kang; Mingming Zhou

doi:10.6180/jase.202003_23(1).0013

Hydraulic characteristics and structural stability of the rotor of a molten-salt pump

Electrical Engineering Mechanical Engineering

Shuang Teng, Can Kang This email address is being protected from spambots. You need JavaScript enabled to view it., Mingming Zhou

School of Energy and Power Engineering, Jiangsu University, Zhenjiang 212013, China

Received: July 22, 2019
Accepted: October 22, 2019
Download Citation: ||https://doi.org/10.6180/jase.202003_23(1).0013

ABSTRACT

To evaluate the operation stability of the centrifugal pump that transports the high-temperature molten salt, the numerical coupling of flow, thermal and structural fields was implemented. Flow characteristics of the pump were investigated using the computational fluid dynamics technique. The stress, deformation and vibration of the pump rotor were solved using the finite element method. Effects of the flow rate of the medium were considered. The results show that the static pressure increases continuously from the impeller inlet to the volute outlet and this trend is remained with the variation in the flow rate. Along the shaft, temperature decreases gradually from the impeller to the bearings. The maximum Von Mises stress in the impeller arises at the connection between the blade and the impeller shroud and decreases as the flow rate increases. The impeller outer edge is responsible for the largest deformation. The deformation of the shaft attenuates from the impeller to the bearings end. The overall deformation of the rotor tends to be mitigated with the increase in the flow rate. The difference is manifested between dominant natural frequencies of the rotor and the blade passing frequency and its harmonics. At low vibration modes, bending of the rotor is predominant. As the mode order increases, torsional vibration patterns of the pump rotor are evidenced.

Keywords: centrifugal pump; molten salt; fluid-thermal-structure coupling; static pressure; stress; deformation

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