bluuebunny/crossref_metadata_2025_split huggingface dataset:
Numerical Investigation on internal flow characteristics of a mixed-flow pump with Tandem malposed blades
Authors: Chenhao Li , Xingqi Luo , Xitong Wu , Guojun Zhu , Like Wang , Xiaohang Wang 
Published: June 2024

Abstract
Mixed-flow pump plays an important role in national major projects and national economic construction. In this paper, a mixed-flow pump is taken as the research object, and the internal flow characteristics and the distribution of turbulent kinetic energy in the pump under different malposed angles of blade are studied by using numerical simulation and blade modification method. The results show that the pump efficiency and head are higher when the tandem blade angles (α) are 15° and 45°, and the pump head is the largest at the α =15°, increasing by 4.37%. Meanwhile, the high-pressure area inside the impeller was large, which had a higher pressurization performance. Under the rated flow condition, the velocity curve of α =15° changes most gently, which is close to the prototype velocity curve, and the single hump zone is not obvious. The tandem malposed blades can restrain the velocity fluctuation and improve the flow field in the impeller. At α =45°, the turbulent kinetic energy dissipation and the velocity fluctuation were the smallest; the flow field was the most stable. The research results have reference significance for the optimal design and selection of mixed flow pump.
Analysis of the Bubble Diameter Effect on the Gas-liquid Flow Characteristics of a Multiphase Rotodynamic Pump
Authors: Li Zhihao , Zhang Wenwu , Zhu Baoshan , Lu Jiaxing , Zhao Haoru 
Published: June 2024

Abstract
In order to study the effect of bubble diameter on the gas-liquid flow in the multiphase rotodynamic pump, steady simulations with different bubble diameters were conducted using ANSYS CFX17.0. When the inlet gas content IGVF is 10%, the pump head and efficiency decrease with the increased inlet bubble diameters, and there are different downward trends at different stages of bubble diameter increase. The pump head and efficiency with small bubble diameter (d≤0.3 mm) are much higher than those of large bubble diameter(d≥0.4 mm). A small amount of gas accumulates on both the blade suction and pressure surfaces near the hub under conditions of small bubble diameters. When the bubble diameter is large, A large amount of gas accumulates on the blade suction surface, and almost no gas accumulates on the blade pressure surface. Due to the density difference between gas and liquid phases, gas accumulates near the hub. The gas content rapidly decreases when away from the hub under small bubble diameter conditions, resulting in good gas-liquid fluidity and weak gas-liquid separation.
Erosion characteristics of a centrifugal pump based on rosin-rammler distribution of particles
Authors: Zhang Haili , Chen Mendi , Xia Guosheng , Tan Lei 
Published: June 2024

Abstract
Centrifugal pumps are widely used in water conservancy, agricultural irrigation and petrochemical fields, but the transferred fluid usually contains solid particles. With prolonged operation in a solid-liquid flow, the components of centrifugal pump are easily eroded, resulting in damaged components, shortened life and reduced efficiency. It is crucial to study the erosion characteristics on centrifugal pump in solid-liquid flow. In this work, based on the particles with Rosin-Rammler distribution in a pump station, the transient operation and erosion process of the centrifugal pump under sandy flow are simulated by using the Eulerian-Lagrangian method and Oka model. Results show that the erosion of R-R distribution is characterized by both large and small particle sizes, but it is closer to the latter condition due to the higher proportion of small particle sizes. The distribution ratio of average erosion rate on hub, blade and shroud is 1.18: 1.68: 1.00, and the most eroded areas are in the leading edge of blade and the trailing edge of the blade suction surface.
Research on the temperature field of a horizontal reactor coolant pump canned motor
Authors: Chen X H , Xu R , Lu J Q , Gong B , Wang D Z 
Published: June 2024

Abstract
The temperature of the flywheel and rolling bearing is a key factor in the stability and safety of the canned motor reactor coolant pump(RCP). The horizontal Canned motor reactor coolant pump (HRCP) is the guarantee of the small modular reactor (SMR) security. HRCP is smaller than traditional RCP, The design of heat shield and flywheel cooling channel reduce the temperature of the flywheel and rolling bearing. In order to calculate the cooling performance of the above two structures. Based on the model,a thermal-fluid-solid coupling method has been used to investigate the safety of the HRCP. Results show that the temperature of the water-lubricated rolling bearing is lower than the allowable temperature; but the temperature of the flywheel is too high. In order to reduce the flywheel temperature, the author proposes a new flywheel cooling channel.it is found that this structure has an obvious effect on reducing the flywheel temperature. This structural design provides a reference for the improvement of the canned motor RCP and the optimization of the flywheel design.
Numerical simulation of start-up and shutdown transient processes of super large flow and high-power centrifugal pump
Authors: Xia Guosheng , Ma Anting , Zhao Xuechu , Fan Honggang , Xu Yu 
Published: June 2024

Abstract
During start-up and shutdown processes, the transient flow of centrifugal pump is complex, which significantly affects the safe and stable operation of the entire pump station. In this paper, considering the effect of the transient process of the pump station, the start-up and shutdown transient processes of a large flow and high-power centrifugal pump was numerically simulated by use of STAR CCM+. The evolution of flow field in the volute and impeller was analyzed. The results show that the flow field of the impeller is filled with complex vortex structures of varying sizes at the beginning of the start-up process of a water pump. As the flow-rate increases, the fluid flow gradually tends to stabilize. During the shutdown process of the water pump, as the flow-rate decreases, the flow field vortices increase progressively, and the flow pattern is unstable. The research results provide a basis for the operation strategy of super large flow and high-power centrifugal pump.
Characteristic analysis of pressure fluctuation of the super large flow and high-power centrifugal pump during transient processes of the start-up and shutdown
Authors: Liu Shuai , Ma Anting , Zhao Xuechu , Fan Honggang , Xu Yu 
Published: June 2024

Abstract
The transient flow field of a super large flow and high-power centrifugal pump during start-up and shutdown is relatively complex and related to the safe and stable operation of the entire water conveyance system. In this study, we conducted a deep analysis of the start-up and shutdown transient processes of a large flow and high-power centrifugal pump. To realize the numerical simulation for the start-up and shutdown transient processes, we used the fluid dynamics calculation and analysis software STAR CCM+. The pressure at multiple monitoring points in the impeller, between stay vanes and impeller, volute, and suction pipe was monitored. In addition, FFT analysis method was used to conduct frequency domain analysis of the pressure at the monitoring points. The changing trend of pressure fluctuation mixing amplitude in the transient processes was discussed. This study provides scientific basis for the safe and stable operation of pump stations.
Experimental and numerical study on erosive wear in a dredge pump impeller
Authors: Guo T , Wang W , Cao L , Xing J 
Published: June 2024

Abstract
Experimental and numerical studies were carried out to study the serious erosive wear occurs in dredge pump impellers. The erosion rate model of medium coarse sand on high chromium cast iron was summarized from the test of gas driven sand impacting wet plate. During conveying tests in a pump-pipe model system, erosive wear in the impeller under the conditions of conveying dense flow of medium coarse sand was measured. A numerical method, in which multiple reference frames is used to treat the rotation of impeller domain and particle-wall reflection is implemented in relative reference frame, is applied to predict the particle trajectories in the model pump, and the erosion wear on the impeller is solved based on the erosion rate model. The wear predicted by numerical method is of the same order of magnitude as that predicted by experimental method, but is significantly lower than the latter. This may be due to the neglect of the wear in the disk clearance and the intensification of local wear caused by mold casting defects in the numerical prediction.
Analysis and application of suppression measures for protection misoperation caused by excitation inrush current of 15.75kV transformer
Authors: Dong J J , Yu T , Chen C J , Huang Y D , Zhong S H 
Published: June 2024

Abstract
This article briefly described the mechanism of transformer magnetizing inrush current, and introduced the principle of differential protection magnetizing inrush current suppression of Siemens 7UT682 protection device. Through the analysis and research of a differential protection malfunction trip event when a no-load closing power of a overhauled transformer, the method of optimizing the relevant parameter configuration of the protection device to avoid the excitation inrush current was proposed and achieved good application results.
A mechanism for efficiently controlling the safety risks of pumped storage power station construction
Authors: Wang H B , Zhang Z J 
Published: June 2024

Abstract
During the construction process of pumped storage power station, the management levels of the participating parties are uneven, and problems such as inaccurate risk identification and unreasonable control measures often occur, which affect the effective operation of the dual prevention mechanism. In order to improve the efficiency and effectiveness of risk management, the author has established a risk database covering the entire life cycle of engineering construction based on the recognition of dangerous and harmful factors in the construction process of pumped storage power station. This greatly enhances the comprehensiveness of risk identification and the effectiveness of measures. At the same time, based on the reasonable allocation of risk management resources according to the task level, information technology tools are used to approve and publish construction work plans, timely release, track and close-loop risk management tasks. Through online processes, the investigation and rectification of hidden dangers are automatically counted, analyzed and tracked, thereby reducing the risk level, eliminating accident hidden dangers, and improving work efficiency.
Mechanism study on the control of cloud cavitation by leading-edge tubercles on NACA0015
Authors: Zhao G S , Liang N , Cao L L , Wu D Z 
Published: June 2024

Abstract
In order to control cloud cavitation, the bio-inspired leading-edge tubercles are implemented on a NACA0015 hydrofoil. The cavitation experiments in a water tunnel are conducted to elaborate on the dynamic behaviors and control mechanisms. As observed, the cavitation with a mean length of 0.38 times chord length on baseline hydrofoil performs three-dimensional features and multiple shedding by the re-entrant jet impingements. Under the equivalent cavitation condition on LET hydrofoil, the cavities with a frothy appearance are produced and confined within the troughs, and the large-scale shedding and re-entrant jet are not identified. The proper orthogonal decomposition (POD) based on cavitation images is carried out to extract the dominant shedding structures. The leading modes of POD on baseline hydrofoil dictate the main shedding of cloud cavitation. The lateral cavities on the LET hydrofoil are well separated by the spanwise periodic tubercles and then the dominant POD modes appear as small-scale vortex pairs. The leading-edge tubercles could depress the three-dimensional cloud cavitation and the re-entrant jets, which is a promising method to control cavitation unsteadiness in hydraulic machinery.
Optimization of rotor blind hole parameters for inner-hole rotary cavitator
Authors: Li Dawei , Yang Yingjie , Ge Ning , Han Guihua , Zhu Yipeng , Jin Di 
Published: June 2024

Abstract
In order to study the cavitation characteristics of rotary cavitator and the optimization of blind hole parameters, this paper first deduces the blind hole geometric parameters (aperture, hole depth, and number of holes) that affect the cavitation effect, then uses a numerical simulation method to optimize the blind hole parameters that affect the cavitation effect based on the control variable method and gas phase contour. Using single factor analysis as the optimization criterion and gas phase volume as the optimization basis, the response surface method was applied to the multi-parameter optimization problem with interaction. The results indicate that the intensity of cavitation can be effectively increased by increasing the geometric dimensions of the blind holes’ diameter, depth, and number appropriately. On the other hand, the response surface method can be utilised to study the multi-parameter optimization problem in the multivariable system comprised of the geometric parameters of the blind hole of the cavitator rotor. This paper’s optimization research on the rotor parameters of inner-hole rotary cavitator provides a foundation and reference for future cavitator structure optimization research.
Numerical investigation on fluid-solid interaction of large-scale centrifugal pumps for pump station
Authors: Liu Shuai , Gao Yuhan , Zhi Yongming , Tan Lei 
Published: June 2024

Abstract
Large-scale centrifugal pumps are significant components in pump stations for water supply projects. In order to figure out the flow and vibration characteristics of large-scale centrifugal pumps, numerical investigation is carried out on the fluid-solid interaction of large-scale centrifugal pumps with stay vanes and adjustable guide vanes. SST k-ω turbulence model is employed to solve turbulent flow inside centrifugal pumps, and the simulated flow fields are imposed on solid impellers by one-way coupling method. The results show that the maximum deformation, maximum stress and maximum strain appear at the impeller outlet with the maximum radius under both schemes of stay vanes and adjustable guide vanes. In addition, compared with the scheme of stay vanes, the non-uniform distribution along circumferential distribution can be suppressed with the equipment of adjustable guide vanes, while the absolute value under adjustable guide vanes is larger than that under stay vanes.
PIV experimental study on water-sediment two-phase flow in NACA0012 cascade
Authors: Zhu Lei , Liu Zhen , Zhang Jianguang , Zhang Haiping , Rao Lei , Lu Li 
Published: June 2024

Abstract
Sediment wear is one of the important reasons for the damage of hydraulic machinery components, and the motion characteristics of sediment are the key factors to determine the degree of wear damage. In order to reveal the mechanism of sediment wear of turbine guide vane, motion characteristics of sediment near the wall of NACA0012 cascade were studied by PIV test method. In this research, fluorescent and sediment particles were used as tracer particles respectively, and the particle images of solid and liquid phases were recorded by double-camera synchronous imaging method. Finally, the synchronous velocity field of solid and liquid phases was determined by correlation analysis of particle images. The experimental results show that the PIV test method can accurately determine the motion characteristics of the solid phase. There is velocity slip between the solid phase and the liquid phase, and the velocity deviation is related to the factors of particle characteristics and Reynolds number.
Finite element numerical analysis of structural vibration of a certain pump station
Authors: Lu Shaopeng , Qiu Haiyun , Lei Xu , Wei Jiang , Fan Honggang 
Published: June 2024

Abstract
In the process of pump station operation, the vibration of factory structure caused by hydraulic or mechanical factors will seriously threaten the ordinary operation of pump station; reduce the efficiency of units; shorten the service lifespan of equipment, and even lead to failure of units. In this paper, ANSYS software and modal analysis method are applied to simulate the vibration effect on pump station under natural vibration, unit vibration excitation and hydraulic excitation. The intrinsic vibration features of pump station structure under diverse boundary conditions, different working conditions and distinct external excitation sources are studied. According to the results of modal and harmonic response analysis, it can be concluded that: 1. A cross relationship has been found existing between pump station structure and unit excitation of speed frequency. 2. In addition to the upper part of the pump station fragile structure, the vibration of the pier is more noteworthy. 3. The vibration amplitude of the whole pump station along vertical direction is larger than that in other directions while the deformation following the unit axis and flow direction presents a strong tendency. 4. In general, the influence of hydraulic load on the structural force of pump station is relatively small.
Stress measurement of runner blade for a Francis prototype turbine
Authors: Cao Dengfeng , Dodge Martin , Zhou Ye , Liu Juan 
Published: June 2024

Abstract
Fatigue crack on the runner blade is one of the severe threats to the operation safety of prototype turbine. Several factor, such as limited operation range, may lead to fatigue cracking commonly observed on Francis turbine. Several cases show that fatigue crack may reduce the working life of runner. The high stress during operation is one of main reasons to produce cracks. Hydraulic design, manufacture quality, deviation of operation condition and resonance may cause high stress on the runner blade. Because static and dynamic stress cannot be predicted with absolute certainty for all operating conditions, the most effective way to obtain the actual stress level of the blade is site measurement. In this paper, stress measurement is carried out on a Francis prototype turbine. Measurement results show that high static stress appears at a load range near full load, and high dynamic stress appears at lower loads. Finally, some practicable suggestions are proposed to reduce the stress of runner blade.
Optimal Design of Data Acquisition System for Fault Diagnosis of Hydraulic Machinery
Authors: Qiu H , Jin B , Zhao W , Wang Z 
Published: June 2024

Abstract
Fault diagnosis of hydraulic machinery has high requirements on the synchronization of monitoring data and the anti-interference of monitoring equipment. The performance and data quality of the existing operation monitoring equipment of the unit cannot meet the requirements. At the same time, due to the variety of sensors and the different wiring methods of different types of sensors, the preparation work such as wiring of data acquisition equipment in the test is complicated. This paper analyzes the application requirements of fault diagnosis data and the problems existing in the conventional data collection process. A data collection solution specified for diagnosis of hydraulic machinery, which better solves the problem of data synchronization, is designed. The new designed system has high sampling accuracy and anti-interference characteristics, as well as the advantages of strong capability and simple equipment deployment. The proposed system has been applied in multiple power stations, pumping stations and pump test platforms. The relevant functions have been effectively verified.
A unit commitment method of pumped storage in renewable energy system via a twofold particle swarm optimization algorithm
Authors: Ji L T , Jing X Y , Wang P , Zhang T , Xiao W D , Qin J , Wang R , Yang W J 
Published: June 2024

Abstract
The problem of unit commitment of pumped storage power stations (UCPS) is rarely discussed in existing works of multi-energy hybrid systems scheduling. It goes against accurately evaluating the operation performance and reliability of the pumped storage unit (PSU). This study proposes a co-optimization scheduling method for a Wind-Photovoltaic-Pumped storage system based on a twofold particle swarm optimization (TPSO). At the system layer, a standard PSO algorithm is used to optimize the output of the pumped storage plant (PSP). At the PSP layer, an improved discrete PSO based on three discrete variables is used to solve the UCPS problem. It uses the constraint patching and the micro-increment rate method, respectively, with detailed consideration of the constraints on PSP and the characteristics of the PSU. Finally, the results of a case study show that refined UCPS can reduce the regulation intensity indicators such as operating duration by more than 25%, with better consistency with the characteristics of units. This work could provide a guideline for improving the operation benefits and reliability of the PSP.
Exploration and application of welding technology for misalignment of pressure pipe orifices in a pumped storage power station
Authors: Mi Haitang , Feng Peilei , Chen Xiaoya , Zhu Anping , Guo Jianqiang , Liu Xiangxiang , Wang Shaohua , Wang Xi 
Published: June 2024

Abstract
Pumped storage power stations are currently the most economical and clean large-scale energy storage method. Pumped storage power stations have flexible start and stop, rapid response, and have six major functions, including peak shaving, valley filling, frequency regulation, phase modulation, emergency backup, and black start. With the transformation of the energy system towards clean, low-carbon, safe and efficient, the operational characteristics of the power system will undergo significant changes, requiring sufficient flexible regulation of power sources and energy storage facilities. It is more urgent to accelerate the development and construction of pumped storage energy. Due to the characteristics of pumped storage installation, high-strength pressure steel pipes are required on the upstream side of the power station units as the water diversion pipeline. This article takes a pumped storage power station as an example to analyze and handle the problem of pipe misalignment encountered during the welding process of pressure steel pipes in the power station. Satisfactory results have been achieved, ensuring the welding quality and providing reference for other engineering projects.
Analysis of Primary Frequency Modulation Performance Test for a Hydropower Station
Authors: Feng Peilei , Chen Xiaoya , Zhu Anping , Guo Jianqiang , Liu Xiangxiang , Wang Shaohua , Huang Shaozheng , Wu Jie , Xu Tianqi , Liu Zhijian 
Published: June 2024

Abstract
To ensure the safe operation of the power grid and generator units, fully utilize the primary frequency regulation capability of the generator units. Enable the grid connected operation team to adapt to changes in grid load and frequency at any time, and improve the control level of power quality and grid frequency. To verify the primary frequency regulation performance of the water turbine generator unit through a frequency regulation test. Test and determine the operating parameters of primary frequency regulation to meet the requirements of primary frequency regulation in the power grid, while ensuring the safe and stable operation of the unit. Provide reference basis for later unit operation through experiments.