Mitigation of high load flow instabilities using axial water jet injection in Francis turbines DOI Open Access
Subodh Khullar, Krishna Mohan Singh, Bhupendra K. Gandhi

et al.

IOP Conference Series Earth and Environmental Science, Journal Year: 2024, Volume and Issue: 1411(1), P. 012058 - 012058

Published: Nov. 1, 2024

Abstract The high load (HL) operations in Francis turbines lead to the inception of unsteady phenomena causing pressure pulsations, vibrations, and cavitation. flow instabilities at HL differ from that part operation (PL). At load, an axisymmetric vortical structure, rotating opposite runner develops draft tube. authors had previously successfully employed axial water jet injection tube mitigate different loads. present numerical work is performed investigate effect on a high-load operating condition. simulations are model turbine unit installed IIT Roorkee. study presents changes velocity distribution along with characteristics, such as efficiency, recovery injection.

Language: Английский

Research on the flow characteristics and energy variation characteristics of the outlet passage of a two-way flow pump device based on Liutex and energy balance equation method DOI
Yuqi Wang, Li Cheng

Energy, Journal Year: 2025, Volume and Issue: 318, P. 134805 - 134805

Published: Jan. 31, 2025

Language: Английский

Citations

1
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

et al.

Physics of Fluids, Journal Year: 2025, Volume and Issue: 37(3)

Published: March 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.

Language: Английский

Citations

1
Staggered impeller configuration effects on energy transfer and pressure stability in two-stage centrifugal pumps for pumped-storage applications DOI
Changliang Ye, Jian Shi,

Dongsen An

et al.

Journal of Energy Storage, Journal Year: 2025, Volume and Issue: 112, P. 115514 - 115514

Published: Jan. 27, 2025

Language: Английский

Citations

0
Impact, analysis, and mitigation of flow instabilities in draft tube of Francis turbines DOI
Subodh Khullar, Krishna Mohan Singh, Michel J. Cervantes

et al.

Physics of Fluids, Journal Year: 2025, Volume and Issue: 37(2)

Published: Feb. 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.

Language: Английский

Citations

0
A potential solution to recover energy from wastewater environment by using the single-channel pump as turbine DOI Creative Commons
Duc-Anh Nguyen, Cong-Τruong Dinh, Gyeong Sung Kim

et al.

Energy, Journal Year: 2025, Volume and Issue: 320, P. 135399 - 135399

Published: March 1, 2025

Language: Английский

Citations

0
Investigation of Blade Number Effect on the Centrifugal Blower as a Small-Scale Water Turbine DOI Open Access

Thoharudin,

THA Santosa,

Hery Irawan

et al.

Journal of Physics Conference Series, Journal Year: 2025, Volume and Issue: 2989(1), P. 012008 - 012008

Published: April 1, 2025

Abstract This study presents a simulation analysis of the impeller blade number effect on air centrifugal blower performed as water turbine at small scale. A with size two inches was modified by varying its to 5, 6, and 7 blades tested underwater flow having three meters elevation. Moreover, different rotational speeds (185, 370, 570 rpm) were evaluated. The installed in reverse improve blade’s aerodynamic performance. results show that more flowed around one half-fold compared experiment due neglecting two-phase (air water) simulation. Increasing speed significantly reduced rate torque raising efficiency. improved performance (torque, power, efficiency) higher rate.

Language: Английский

Citations

0
Intensity recognition of vortex ropes in draft tube of a prototype pump turbine using an optimized CNN-BiLSTM framework with multi-head self-attention mechanism DOI

Xianjue Zheng,

Chenxin Yang,

Lan Zeng

et al.

Journal of Energy Storage, Journal Year: 2024, Volume and Issue: 106, P. 114910 - 114910

Published: Dec. 4, 2024

Language: Английский

Citations

0
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

et al.

IOP Conference Series Earth and Environmental Science, Journal Year: 2024, Volume and Issue: 1411(1), P. 012005 - 012005

Published: Nov. 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.

Language: Английский

Citations

0
Mitigation of high load flow instabilities using axial water jet injection in Francis turbines DOI Open Access
Subodh Khullar, Krishna Mohan Singh, Bhupendra K. Gandhi

et al.

IOP Conference Series Earth and Environmental Science, Journal Year: 2024, Volume and Issue: 1411(1), P. 012058 - 012058

Published: Nov. 1, 2024

Abstract The high load (HL) operations in Francis turbines lead to the inception of unsteady phenomena causing pressure pulsations, vibrations, and cavitation. flow instabilities at HL differ from that part operation (PL). At load, an axisymmetric vortical structure, rotating opposite runner develops draft tube. authors had previously successfully employed axial water jet injection tube mitigate different loads. present numerical work is performed investigate effect on a high-load operating condition. simulations are model turbine unit installed IIT Roorkee. study presents changes velocity distribution along with characteristics, such as efficiency, recovery injection.

Language: Английский

Citations

0