Influence of labyrinth clearance on the hydrodynamic performance of a high head Francis turbine DOI Open Access
Md Mustafa Kamal,

Luciano Devinar,

Ahmed M. Abbas

и другие.

IOP Conference Series Earth and Environmental Science, Год журнала: 2024, Номер 1411(1), С. 012005 - 012005

Опубликована: Ноя. 1, 2024

Abstract Francis turbines have a leakage loss from the corresponding labyrinth seals i.e., crown side and skirt clearance. Therefore, clearance between runner turbine cover plays an important role in hydrodynamic characteristics of hydro turbine. Generally, geometrical details are not considered numerical model due to complexity involved modelling requirement high computational power that may lead inaccurate prediction performance In present investigation, steady-state simulations been performed on head turbine, under different operating conditions, ranging part load overload condition, assess influence FVM method (as discretization method) along with SST k-omega turbulence has adopted for modelling. The simulation results such as hydraulic efficiency output validated test which was done per IEC 60193 standard found satisfactory agreement. Further, axial thrust force is also computed conditions compared results. Based results, it 0.4% - 1.1% lower than without higher at part-load condition other conditions. It observed almost same all loading particular fall range 0.61% 0.81%. value increases discharge maximum 203 kN condition.

Язык: Английский

Towards the pumped-hydro energy storage: improvement on the flow instability and cavitation performance with application-oriented forward skew angle of impeller blades DOI
Weixiang Ye, Huan Liu, Hong Wang

и другие.

Energy, Год журнала: 2025, Номер unknown, С. 134565 - 134565

Опубликована: Янв. 1, 2025

Язык: Английский

Процитировано

3

Effect of return channel on performance and pressure fluctuation of pump turbine DOI
Wenjie Wang,

Gai Qiu,

Ji Pei

и другие.

Physics of Fluids, Год журнала: 2024, Номер 36(10)

Опубликована: Окт. 1, 2024

To stabilize the operation of pumped storage power station, an orthogonal experimental design was proposed to optimize return channel with splitter blades pump turbine. The calculation results various models under multiple operating conditions indicated that inlet distance a1 and blade number z considerably affect efficiency flow pattern in passage. optimal scheme improved by nearly 3% at 0.6Qd. Savitzky–Golay filtering method Fast Fourier Transform were used analyze unsteady characteristics turbine model. amplitude pressure pulsations passing frequency vaneless space interference zone between guide vane reduced considerably, pulsation decreased 50%, 48%, 20% for 0.6Qd, 1.0Qd, 1.1Qd conditions. A Continuous Wavelet signals during shutdown transition process. optimization their corresponding passages suppressed high-amplitude unit stable station.

Язык: Английский

Процитировано

14

Effects of vortex rope formation in draft tube of reversible pump-turbine – A review DOI
Bhushan R. Rode, Arun Kumar

Journal of Energy Storage, Год журнала: 2024, Номер 99, С. 113250 - 113250

Опубликована: Авг. 8, 2024

Язык: Английский

Процитировано

10

Rotor-stator interaction and vortex rope in the high-head variable speed reversible pump-turbine operating at minimum head DOI
Bhushan R. Rode, Arun Kumar,

Claire Ségoufin

и другие.

Physics of Fluids, Год журнала: 2025, Номер 37(3)

Опубликована: Март 1, 2025

The pumped storage hydropower (PSHP) has large head variations during its cyclic operation, and using variable speed units of reversible pump turbines (RPT) can extend operating range grid stability. In minimum conditions, the performance RPT in turbine mode is more important because it may experience fatigue vibrations due to hydraulic instabilities caused by rotor-stator interaction (RSI) vaneless space vortex rope draft tube. Therefore, investigate these phenomena RPTs at head. At flow rate, controller adjusts rotational value that yields highest efficiency, becomes “fixed” condition. present work investigates RSI associated pressure fluctuations (PFs) available conditions. analysis was performed best efficiency point (BEP) with three rates having fixed (corresponding efficiency). It observed fluctuates as a result presence low-pressure stagnation region inlet side runner blade. developed tube center high-velocity gradient. be concluded main source PF condition RSI.

Язык: Английский

Процитировано

2

Investigation on the characteristics and formation mechanism of backflow in S-shaped region of a reversible pump-turbine DOI

Zehui Zhu,

Qi Gu,

Dongrui Wang

и другие.

Physics of Fluids, Год журнала: 2025, Номер 37(2)

Опубликована: Фев. 1, 2025

When reversible pump turbines go through the S-shape region, there is some significant backflow regions in vaneless space, accompanied by severe pressure fluctuation. However, internal correlation and mutual influence mechanism among fluctuation, turbulent vortex structure, are still unclear enough current research. In this work, characteristics formation of turbine region figured out using computational fluid dynamics methods. The results indicate that Leading-Edge-Passage-Vortex caused adverse gradient dominant initial stage backflow. stage, interaction between inflow main reason causing high amplitude wideband fluctuation components space. development, centrifugal force play roles different regions, respectively. rotating stall phenomenon appears runner a low-frequency component 0.6fn 0.3fn∼0.45fn appeared, respectively, space runner. fully developed dominated concentrated flow area inlet, while pushed to upper crown lower ring. These findings can provide theoretical supports for improving stability operating off-design condition.

Язык: Английский

Процитировано

1

Hydraulic oscillations and stability testing of a novel shaft coaxial surge chamber with small load disturbances in pumped storage power stations DOI

Wu Zhao,

Jian Zhang, Sheng Chen

и другие.

Physics of Fluids, Год журнала: 2025, Номер 37(1)

Опубликована: Янв. 1, 2025

Surge chambers play a critical role in moderating oscillations pumped storage power stations after load disturbances. Owing to the high costs, increased risks, and extended construction times associated with conventional surge (CSCs), we proposed shaft coaxial chamber (SCSC) as an alternative, which was otherwise compact, economical, construction-friendly structural configuration. The present study aimed investigate hydraulic oscillations, stability, flow characteristics of SCSC compared CSC under disturbance conditions. Physical models both types were developed validated. results indicated that novel system could maintain stability before disturbances; its fluctuations slightly higher than those CSC, particularly pumping During disturbance, water level fluctuation amplitudes at least 1.43 2.24 different working conditions 10% disturbance. As frequency increased, approached CSC. Moreover, new discharge coefficient range 0.9–1.2 for proposed, increasing standard values by 1.5 times. In conclusion, unstable patterns connecting pipe are mechanisms influence SCSC. These findings provide valuable theoretical guidance practical applications.

Язык: Английский

Процитировано

0

Multi-scale flow-induced dynamic response in 710-MW Francis turbine: numerical investigation DOI
Kan Kan,

Yunkuan Yu,

Yu Chen

и другие.

International Journal of Mechanical Sciences, Год журнала: 2025, Номер unknown, С. 110345 - 110345

Опубликована: Май 1, 2025

Язык: Английский

Процитировано

0

Numerical investigation on the unstable flow and its interaction with the hump characteristic in a pump turbine at pump mode DOI
Weixiang Ye, Zhaohui Qian, Yongshun Zeng

и другие.

Journal of Energy Storage, Год журнала: 2024, Номер 101, С. 113853 - 113853

Опубликована: Сен. 24, 2024

Язык: Английский

Процитировано

2

Effect of Speed Linear Decrease on Internal Flow Characteristics and Pressure Pulsations of Variable-Speed Pump Turbine in Turbine Mode DOI Creative Commons
Guangtai Shi,

Binyan Li,

Yexiang Xiao

и другие.

Journal of Marine Science and Engineering, Год журнала: 2024, Номер 12(12), С. 2243 - 2243

Опубликована: Дек. 6, 2024

Pumped storage units often deviate from the optimal operating conditions in process of regulating new energy fluctuations. To effectively improve performance units, variable speed is one more feasible means at present. This paper focuses on part-load condition turbine operation, with an emphasis internal flow characteristics and pressure pulsation pump during linear reduction rated speed. It found that streamlines runner become turbulent reduction, forming a vortex inlet runner, scale gradually increases reduction. The rope draft tube undergoes three types changes reduction: helical eccentric rope, vanishing columnar rope. Before change, low-frequency components high amplitude exist each flow-passing part, but disappear Except for frequency affected by rotor–stator interference part decrease speed, growth most obvious vaneless region. findings this research can serve as valuable reference operation pumped units.

Язык: Английский

Процитировано

1

Numerical study of pressure fluctuation in vaneless space of variable speed reversible pump-turbine in turbine mode at maximum head DOI Open Access
Bhushan R. Rode, Arun Kumar,

Claire Ségoufin

и другие.

IOP Conference Series Earth and Environmental Science, Год журнала: 2024, Номер 1411(1), С. 012028 - 012028

Опубликована: Ноя. 1, 2024

Abstract Efficiency and grid stability of pumped storage plants with significant head variations can be enhanced by the implementation variable speed operation. The reversible pump-turbine (RPT) operating in turbine mode is particularly prone to fatigue vibrations when at maximum conditions, primarily due hydraulic instabilities caused pressure fluctuations vaneless space thus, performance RPT becomes increasingly critical under such conditions. It is, therefore, important examine RPTs higher heads. findings indicate that main source across all conditions rotor-stator interaction (RSI), where dominant frequency blade passing (9 f n ) its harmonics.

Язык: Английский

Процитировано

1