Reliability Engineering & System Safety, Год журнала: 2024, Номер 254, С. 110607 - 110607
Опубликована: Ноя. 7, 2024
Язык: Английский
Reliability Engineering & System Safety, Год журнала: 2024, Номер 254, С. 110607 - 110607
Опубликована: Ноя. 7, 2024
Язык: Английский
Journal of Energy Storage, Год журнала: 2024, Номер 94, С. 112385 - 112385
Опубликована: Июнь 13, 2024
Язык: Английский
Процитировано
40Physics of Fluids, Год журнала: 2024, Номер 36(3)
Опубликована: Март 1, 2024
Efficiency and grid stability can be improved by variable speed operation using doubly fed induction machine technology for pumped storage plants experiencing significant head variations. With the higher penetration of intermittent renewable energy sources, viz., solar wind, may stabilized operating reversible pump-turbines (RPTs) in off-design conditions. In a turbine mode, RPT is more susceptible to fatigue vibrations when at as result hydraulic instability generated rotor–stator interaction (RSI); therefore, its performance becomes even critical. The powerhouse structural components, including floors columns, could experience intense because this instability. Therefore, it essential investigate RSI RPTs head. These investigations present results numerical analysis associated pressure fluctuations high-head scaled model was used, simulations were executed utilizing shear stress transport k-ω turbulence model. performed best efficiency point conditions having optimized rotational speed. show that main source all RSI, where dominant frequencies are blade passing frequency (9fn) harmonics. It also found lowers RPT.
Язык: Английский
Процитировано
11Journal of Energy Storage, Год журнала: 2024, Номер 99, С. 113250 - 113250
Опубликована: Авг. 8, 2024
Язык: Английский
Процитировано
10Physics of Fluids, Год журнала: 2025, Номер 37(2)
Опубликована: Фев. 1, 2025
Hydropower is a clean, renewable, and highly efficient energy source accounts for about 16% of global electricity production. Apart from baseload generation, hydraulic turbines are more often subjected to less off-design operating conditions handle the fluctuating demands stabilize power grid. These sub-optimal operations result in flow instabilities such as vortex breakdown inter-blade vortices, which reduce overall efficiency produce severe pressure pulsations. This review summarizes various forms theories developed explain phenomena. The impact these on turbine operation discussed. Mathematical models describe swirling flows downstream Francis runner also presented. Parameters that influence characteristics outlined. concludes with discussion methods alleviate adverse effects turbines.
Язык: Английский
Процитировано
2Physics 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
2Energies, Год журнала: 2025, Номер 18(2), С. 394 - 394
Опубликована: Янв. 17, 2025
As the core for energy conversion in pumped storage plants, pump turbine is also a key component process of building clean power grid, owing to its fast and accurate load regulation. This paper introduces current status research development turbines from perspectives significance, design optimization, operational performance, advanced methods, etc. Internal external characteristics such as transient flow evolution, structural vibration, flow-induced noise, etc., not only reflect performance (hydraulic, cavitation, sediment abrasion, stability etc.) but directly affect safe efficient operation system. It worth mentioning that space-time evolution internal an emerging direction, results which can be used predict conditions turbines. Moreover, application intelligent condition monitoring fault diagnosis aim prevent failures accidents plants.
Язык: Английский
Процитировано
1Physics 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
1Journal of Energy Storage, Год журнала: 2024, Номер 86, С. 111358 - 111358
Опубликована: Март 26, 2024
Язык: Английский
Процитировано
8Physics of Fluids, Год журнала: 2024, Номер 36(4)
Опубликована: Апрель 1, 2024
To investigate the adverse effects of rotating stalls on pressure pulsation characteristics a pump-turbine in pump mode, an unsteady numerical simulation was carried out by applying partially averaged Navier–Stokes turbulence model. The methods were carefully verified, and onset flow rate hump at performance curve heads good agreement with experimental data. stall appeared guide vane when ranged from 0.514 to 0.887 times best efficiency point (QBEP), frequency 11.7% rotational frequency. In period stall, sudden intensive channel observed named as component broadband frequency, its corresponding mechanism explained vortex evolution between adjacent blades based dynamic mode decomposition technology. There three distinct frequency: (i) intermittent occurrence cell propagated current channel, (ii) wide range varying rate, (iii) considerable amplitude, e.g., reaching 21.1%–42.2% that addition, both amplitude gradually decreased increased 0.887QBEP. This study clarified internal behaviors if occurred, which important assess stability units.
Язык: Английский
Процитировано
7Journal of Energy Storage, Год журнала: 2024, Номер 99, С. 113447 - 113447
Опубликована: Авг. 29, 2024
Язык: Английский
Процитировано
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