IDEAS home Printed from https://ideas.repec.org/a/eee/renene/v188y2022icp1166-1183.html
   My bibliography  Save this article

Flow-induced pulsations in Francis turbines during startup - A consequence of an intermittent energy system

Author

Listed:
  • Salehi, Saeed
  • Nilsson, Håkan

Abstract

Hydraulic turbines are increasingly responsible for regulating the electric grid, due to the rapid growth of the intermittent renewable energy resources. This involves a large increase in the number of starts and stops, which cause severe flow-induced pulsations and fluctuating forces that deteriorate the machines. Better knowledge of the evolution of the flow in the machines during transients makes it possible to avoid hazardous conditions, plan maintenance intervals, and estimate the costs of this new kind of operation. The present work provides an in-depth and comprehensive numerical study on the flow-induced pulsations and evolution of the flow field in a high-head model Francis turbine during a startup sequence. The flow simulation is carried out using the OpenFOAM open-source CFD code. A thorough frequency analysis is conducted on the fluctuating part of different pressure probes and force components, utilizing Short-Time Fourier Transform (STFT) to extract the evolution of the frequency and amplitude of pulsations. Low-frequency oscillations are detected during the startup, which are induced by the complex flow structure in the draft tube. A decomposition is performed on the draft tube pressure signals, and the variations of the synchronous (plunging) and asynchronous (rotating) modes are studied. The plunging mode is stronger at minimum and deep part load conditions, whereas the rotating mode is dominant during the presence of the Rotating Vortex Rope (RVR) at part load. The velocity field in the draft tube is validated against experimental data, and the complex flow structures formed during the startup procedure are explained using the λ2 vortex identification method.

Suggested Citation

  • Salehi, Saeed & Nilsson, Håkan, 2022. "Flow-induced pulsations in Francis turbines during startup - A consequence of an intermittent energy system," Renewable Energy, Elsevier, vol. 188(C), pages 1166-1183.
    • Handle: RePEc:eee:renene:v:188:y:2022:i:c:p:1166-1183
    DOI: 10.1016/j.renene.2022.01.111
    as

    Download full text from publisher

    File URL: http://www.sciencedirect.com/science/article/pii/S0960148122001215
    Download Restriction: Full text for ScienceDirect subscribers only
    File URL: https://libkey.io/10.1016/j.renene.2022.01.111?utm_source=ideas
    LibKey link: if access is restricted and if your library uses this service, LibKey will redirect you to where you can use your library subscription to access this item
    ---><---

    As the access to this document is restricted, you may want to search for a different version of it.

    References listed on IDEAS

    as
    1. Salehi, Saeed & Nilsson, Håkan & Lillberg, Eric & Edh, Nicolas, 2021. "An in-depth numerical analysis of transient flow field in a Francis turbine during shutdown," Renewable Energy, Elsevier, vol. 179(C), pages 2322-2347.
    2. Unterluggauer, Julian & Sulzgruber, Verena & Doujak, Eduard & Bauer, Christian, 2020. "Experimental and numerical study of a prototype Francis turbine startup," Renewable Energy, Elsevier, vol. 157(C), pages 1212-1221.
    3. Sotoudeh, Nahale & Maddahian, Reza & Cervantes, Michel J., 2020. "Investigation of Rotating Vortex Rope formation during load variation in a Francis turbine draft tube," Renewable Energy, Elsevier, vol. 151(C), pages 238-254.
    4. Caralis, G. & Papantonis, D. & Zervos, A., 2012. "The role of pumped storage systems towards the large scale wind integration in the Greek power supply system," Renewable and Sustainable Energy Reviews, Elsevier, vol. 16(5), pages 2558-2565.
    5. Goyal, Rahul & Gandhi, Bhupendra K., 2018. "Review of hydrodynamics instabilities in Francis turbine during off-design and transient operations," Renewable Energy, Elsevier, vol. 116(PA), pages 697-709.
    Full references (including those not matched with items on IDEAS)

    Citations

    Citations are extracted by the CitEc Project, subscribe to its RSS feed for this item.
    as


    Cited by:

    1. Sun, Longgang & Xu, Hongyang & Li, Chenxi & Guo, Pengcheng & Xu, Zhuofei, 2024. "Unsteady assessment and alleviation of inter-blade vortex in Francis turbine," Applied Energy, Elsevier, vol. 358(C).

    Most related items

    These are the items that most often cite the same works as this one and are cited by the same works as this one.
    1. Salehi, Saeed & Nilsson, Håkan, 2022. "Effects of uncertainties in positioning of PIV plane on validation of CFD results of a high-head Francis turbine model," Renewable Energy, Elsevier, vol. 193(C), pages 57-75.
    2. Salehi, Saeed & Nilsson, Håkan & Lillberg, Eric & Edh, Nicolas, 2021. "An in-depth numerical analysis of transient flow field in a Francis turbine during shutdown," Renewable Energy, Elsevier, vol. 179(C), pages 2322-2347.
    3. Su, Wen-Tao & Binama, Maxime & Li, Yang & Zhao, Yue, 2020. "Study on the method of reducing the pressure fluctuation of hydraulic turbine by optimizing the draft tube pressure distribution," Renewable Energy, Elsevier, vol. 162(C), pages 550-560.
    4. Alerci, A.L. & Vagnoni, E. & Paolone, M., 2023. "Structural impact of the start-up sequence on Pelton turbines lifetime: Analytical prediction and polynomial optimization," Renewable Energy, Elsevier, vol. 218(C).
    5. Sun, Longgang & Xu, Hongyang & Li, Chenxi & Guo, Pengcheng & Xu, Zhuofei, 2024. "Unsteady assessment and alleviation of inter-blade vortex in Francis turbine," Applied Energy, Elsevier, vol. 358(C).
    6. Raluca Gabriela Iovănel & Arash Soltani Dehkharqani & Diana Maria Bucur & Michel Jose Cervantes, 2022. "Numerical Simulation and Experimental Validation of a Kaplan Prototype Turbine Operating on a Cam Curve," Energies, MDPI, vol. 15(11), pages 1-24, June.
    7. Wang, Huan & Li, Wenfeng & Hou, Yaochun & Wu, Peng & Huang, Bin & Wu, Kelin & Wu, Dazhuan, 2023. "Recognition of the developing vortex rope in Francis turbine draft tube based on PSO-CS2," Renewable Energy, Elsevier, vol. 217(C).
    8. Zhumei Luo & Cong Nie & Shunli Lv & Tao Guo & Suoming Gao, 2022. "The Effect of J-Groove on Vortex Suppression and Energy Dissipation in a Draft Tube of Francis Turbine," Energies, MDPI, vol. 15(5), pages 1-20, February.
    9. Borkowski, Dariusz & Węgiel, Michał & Ocłoń, Paweł & Węgiel, Tomasz, 2019. "CFD model and experimental verification of water turbine integrated with electrical generator," Energy, Elsevier, vol. 185(C), pages 875-883.
    10. Rafel Roig & Xavier Sánchez-Botello & Xavier Escaler & Berhanu Mulu & Carl-Maikel Högström, 2022. "On the Rotating Vortex Rope and Its Induced Structural Response in a Kaplan Turbine Model," Energies, MDPI, vol. 15(17), pages 1-19, August.
    11. He, Xianghui & Yang, Jiandong & Yang, Jiebin & Zhao, Zhigao & Hu, Jinhong & Peng, Tao, 2023. "Evolution mechanism of water column separation in pump turbine: Model experiment and occurrence criterion," Energy, Elsevier, vol. 265(C).
    12. Ma, Tao & Yang, Hongxing & Lu, Lin & Peng, Jinqing, 2014. "Technical feasibility study on a standalone hybrid solar-wind system with pumped hydro storage for a remote island in Hong Kong," Renewable Energy, Elsevier, vol. 69(C), pages 7-15.
    13. Zhang, Sufang & Andrews-Speed, Philip & Perera, Pradeep, 2015. "The evolving policy regime for pumped storage hydroelectricity in China: A key support for low-carbon energy," Applied Energy, Elsevier, vol. 150(C), pages 15-24.
    14. Eduard Doujak & Anton Maly & Julian Unterluggauer & Franz Haller & Michael Maier & Christian Blasbichler & Simon Stadler, 2023. "Fatigue Strength Analysis of a Prototype Francis Turbine in a Multilevel Lifetime Assessment Procedure Part III: Instrumentation and Prototype Site Measurement," Energies, MDPI, vol. 16(16), pages 1-39, August.
    15. Solomon, A.A. & Kammen, Daniel M. & Callaway, D., 2016. "Investigating the impact of wind–solar complementarities on energy storage requirement and the corresponding supply reliability criteria," Applied Energy, Elsevier, vol. 168(C), pages 130-145.
    16. K., Subramanya & Chelliah, Thanga Raj, 2023. "Capability of synchronous and asynchronous hydropower generating systems: A comprehensive study," Renewable and Sustainable Energy Reviews, Elsevier, vol. 188(C).
    17. Anuja Shaktawat & Shelly Vadhera, 2021. "Risk management of hydropower projects for sustainable development: a review," Environment, Development and Sustainability: A Multidisciplinary Approach to the Theory and Practice of Sustainable Development, Springer, vol. 23(1), pages 45-76, January.
    18. Kim, Seung-Jun & Yang, Hyeon-Mo & Park, Jungwan & Kim, Jin-Hyuk, 2022. "Investigation of internal flow characteristics by a Thoma number in the turbine mode of a Pump–Turbine model under high flow rate," Renewable Energy, Elsevier, vol. 199(C), pages 445-461.
    19. Javed, Muhammad Shahzad & Ma, Tao & Jurasz, Jakub & Amin, Muhammad Yasir, 2020. "Solar and wind power generation systems with pumped hydro storage: Review and future perspectives," Renewable Energy, Elsevier, vol. 148(C), pages 176-192.
    20. Pei, Ji & Shen, Jiawei & Wang, Wenjie & Yuan, Shouqi & Zhao, Jiantao, 2024. "Evaluating hydraulic dissipation in a reversible mixed-flow pump for micro-pumped hydro storage based on entropy production theory," Renewable Energy, Elsevier, vol. 225(C).

    Corrections

    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:eee:renene:v:188:y:2022:i:c:p:1166-1183. See general information about how to correct material in RePEc.

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    If CitEc recognized a bibliographic reference but did not link an item in RePEc to it, you can help with this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: Catherine Liu (email available below). General contact details of provider: http://www.journals.elsevier.com/renewable-energy .

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service. RePEc uses bibliographic data supplied by the respective publishers.