Influence of the Impeller/Guide Vane Clearance Ratio on the Performances of a Nuclear Reactor Coolant Pump

To study the effects of guide vane with different vane wrap angles and relative positions of outlet edge on hydraulic performance of nuclear reactor coolant pump, three-dimensional steady numerical simulations were performed by using CFD commercial software Numeca. The results show that the vane wrap angle changes the head and power characteristics by changing the relative velocity angle in vane outlet. The inner flow field changes while the wrap angle changes. With the wrap angle increases, the shock loss in volute is reducing, but the friction loss in vane passages is getting large. So there exists an optimum wrap angle and relative positions of outlet edge that corresponds to the highest efficiency of a pump. Numerical simulation is performed with the two key design parameters optimized through surrogate model, the internal flow field is improved and then the hydraulic efficiency is improved.

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Influence of Circumferential Placement Position of Guide Vanes on Performance and Dynamic Characteristics of Nuclear Reactor Coolant Pump

Mathematical Problems in Engineering ◽

10.1155/2020/3786745 ◽

2020 ◽

Vol 2020 ◽

pp. 1-12

Author(s):

Xiaorui Cheng ◽

Boru Lv ◽

Chenying Ji ◽

Ningning Jia ◽

Dorah N

Keyword(s):

Nuclear Reactor ◽

Guide Vane ◽

Equivalent Stress ◽

Hydraulic Loss ◽

Stress Strain ◽

Coolant Pump ◽

Guide Vanes ◽

Reactor Coolant ◽

Maximum Equivalent Stress ◽

Exit Edge

In order to study the influence of the circumferential placement position of the guide vane on the flow field and stress-strain of a nuclear reactor coolant pump, the CAP1400 nuclear reactor coolant pump is taken as the research object. Based on numerical calculation and test results, the influence of circumferential placement position of the guide vane on the performance of the nuclear reactor coolant pump and stress-strain of guide vanes are analyzed by the unidirectional fluid-solid coupling method. The results show that the physical model and calculation method used in the study can accurately reflect the influence of the circumferential placement position of the guide vane on the nuclear reactor coolant pump. In the design condition, guide vane position has a great influence on the nuclear reactor coolant pump efficiency value, suction surface of the guide vane blade, and the maximum equivalent stress on the hub. However, it has a weak effect on the head value, pressure surface of the guide vane blade, and the maximum equivalent stress on the shroud. When the center line of the outlet diffuser channel of the case is located at the center of the outlet of flow channel of the guide vane, it is an optimal guide vane circumferential placement position, which can reduce the hydraulic loss of half of the case. Finally, it is found that the high stress concentration area is at the intersection of the exit edge of the vane blade and the front and rear cover, and the exit edge of the guide vane blade and its intersection with the front cover are areas where the strength damage is most likely to occur. This study provides a reference for nuclear reactor coolant pump installation, shock absorption design, and structural optimization.

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Mathematical Modelling Forecast on the Idling Transient Characteristic of Reactor Coolant Pump

Processes ◽

10.3390/pr7070452 ◽

2019 ◽

Vol 7 (7) ◽

pp. 452 ◽

Cited By ~ 1

Author(s):

Wang ◽

Xie ◽

Lu ◽

Zhu ◽

Fu ◽

...

Keyword(s):

Transient Flow ◽

Guide Vane ◽

Characteristic Curve ◽

Hydraulic Modeling ◽

Modeling Framework ◽

Coolant Pump ◽

Important Indicator ◽

Reactor Coolant ◽

Power Failure ◽

Accident Condition

The idling behavior of the reactor coolant pump is referred to as an important indicator of the safe operation of the nuclear power system, while the idling transition process under the power failure accident condition is developed as a transient flow process. In this process, the parameters such as the flow rate, speed, and head of the reactor coolant pump are all nonlinear changes. In order to ensure the optimal idling behavior of the reactor coolant pump under the power cutoff accident condition, this manuscript takes the guide vanes of the AP1000 reactor coolant pump as the subject of this study. In this paper, the mathematical model of idling speed and flow characteristic curve of reactor coolant pump under the power failure condition were proposed, while the hydraulic modeling database of different vane structure parameters was modeled based on the orthogonal optimization schemes. Furthermore, based on the mathematical modeling framework of multiple linear regressions, the mathematical relationship of the hydraulic performance of each guide vane in different parameters was predicted. The derived model was verified with the idling test data.

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Study on pressure pulsation characteristics of reactor coolant pump during the idling transition process

Journal of Vibration and Control ◽

10.1177/1077546319858856 ◽

2019 ◽

Vol 25 (18) ◽

pp. 2509-2522 ◽

Cited By ~ 1

Author(s):

Xiuli Wang ◽

Yonggang Lu ◽

Rongsheng Zhu ◽

Yuanyuan Zhao ◽

Qiang Fu

Keyword(s):

Pressure Pulsation ◽

Transient Flow ◽

Guide Vane ◽

Transition Process ◽

Dynamics Simulation ◽

Discrete Wavelet ◽

Flow Process ◽

Coolant Pump ◽

Rotating Speed ◽

Reactor Coolant

The idling characteristic of the reactor coolant pump is one of the important indicators for the safe operation of the nuclear power system. The idling transition process of the reactor coolant pump under the power failure accident condition belongs to the transient flow process. During most of the time of the idling transition process, the parameters of flow, rotating speed, and head are all nonlinear changes, and the study of the idling change law is extremely difficult. This paper introduces the nonlinear inertia transient phase of the reactor coolant pump and the principle of wavelet analysis. Based on the experimental results of the idling transition process, the polynomial fitting of the flow curve and the rotating speed curve is fitted, and the idling transient equation is established which is a boundary condition for computational fluid dynamics simulation of the nonlinear idling transient stage of the reactor coolant pump with different types of guide vanes. The signal fluctuation of pressure pulsation time-domain change at the volute outlet in different sub-bands is analyzed by means of a fast, discrete wavelet transform, and the effects of different vane optimizations in different idling stages are analyzed. It was found that the pressure fluctuation amplitude of each sub-frequency range of pump outlet in the model of the shunt guide vane is significantly smaller than that of the normal guide vane.

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