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Influence of upstream disturbance on the draft-tube flow of Francis turbine under part-load conditions

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Abstract

Owing to the part-load operations for the enhancement of grid flexibility, the Francis turbine often suffers from severe low-frequency and large-amplitude hydraulic instability, which is mostly pertinent to the highly unsteady swirling vortex rope in the draft tube. The influence of disturbances in the upstream (e.g., large-scale vortex structures in the spiral casing) on the draft-tube vortex flow is not well understood yet. In the present paper, the influence of the upstream disturbances on the vortical flow in the draft tube is studied based on the vortex identification method and the analysis of several important parameters (e.g., the swirl number and the velocity profile). For a small guide vane opening (representing the part-load condition), the vortices triggered in the spiral casing propagate downstream and significantly affect the swirling vortex-rope precession in the draft tube, leading to the changes of the intensity and the processional frequency of the swirling vortex rope. When the guide vane opening approaches the optimum one (representing the full-load condition), the upstream disturbance becomes weaker and thus its influences on the downstream flow are very limited.

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References

  1. Zhang Y., Tang N., Niu Y. et al. Wind energy rejection in China: Current status, reasons and perspectives [J]. Renewable and Sustainable Energy Reviews, 2016, 66(12): 322–344.

    Article  Google Scholar 

  2. Zhang Y., Zhang Y., Wu Y. A review of rotating stall in reversible pump turbine [J]. Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, 2017, 231(7): 1181–1204.

    Google Scholar 

  3. Zhang Y., Chen T., Li J. et al. Experimental study of load variations on pressure fluctuations in a prototype reversible pump turbine in generating mode [J]. Journal of Fluids Engineering, 2017, 139(7): 074501.

    Article  Google Scholar 

  4. Escudier M. Confined vortices in flow machinery [J]. Annual Review of Fluid Mechanics, 1987, 19(1): 27–52.

    Article  Google Scholar 

  5. Dörfler P., Sick M., Coutu A. Flow-induced pulsation and vibration in hydroelectric machinery: Engineer’s guidebook for planning, design and troubleshooting [M]. London, UK: Springer-Verlag, 2013.

    Book  Google Scholar 

  6. Wu Y., Li S., Liu S. et al. Vibration of hydraulic machinery [M]. Dordrecht, The Netherlands: Springer Science+Business Media, 2013.

    Book  Google Scholar 

  7. Foroutan H., Yavuzkurt S. An axisymmetric model for draft tube flow at partial load [J]. Journal of Hydrodynamics, 2016, 28(2): 195–205.

    Article  Google Scholar 

  8. Susan-Resiga R., Muntean S., Hasmatuchi V. et al. Analysis and prevention of vortex breakdown in the simplified discharge cone of a Francis turbine [J]. Journal of Fluids Engineering, 2010, 132(5): 051102.

    Article  Google Scholar 

  9. Li S. Cavitation of hydraulic machinery [M]. London, UK: Imperial College Press, 2000.

    Book  Google Scholar 

  10. Escaler X., Egusquiza E., Farhat M. et al. Detection of cavitation in hydraulic turbines [J]. Mechanical Systems and Signal Processing, 2006, 20(4): 983–1007.

    Article  Google Scholar 

  11. Li S. Tiny bubbles challenge giant turbines: Three Gorges puzzle [J]. Interface Focus, 2015, 5(5): 20150020.

    Article  Google Scholar 

  12. Cassidy J., Falvey H. Observations of unsteady flow arising after vortex breakdown [J]. Journal of Fluid Mechanics, 1970, 41: 727–736.

    Article  Google Scholar 

  13. Nishi M. Surging characteristics of conical and elbow type draft tubes [C]. Proceedings of the 12th IAHR Symposium on Hydraulic Machinery and System, Stirling, UK, 1984, 272–283.

    Google Scholar 

  14. Alekseenko S., Kuibin P., Okulov V. et al. Helical vortices in swirl flow [J]. Journal of Fluid Mechanics, 1999, 382: 195–243.

    Article  MathSciNet  MATH  Google Scholar 

  15. Benjamin T. Theory of the vortex breakdown phenomenon [J]. Journal of Fluid Mechanics, 1962, 14: 593–629.

    Article  MathSciNet  Google Scholar 

  16. Anup K., Lee Y., Thapa B. CFD study on prediction of vortex shedding in draft tube of Francis turbine and vortex control techniques [J]. Renewable Energy, 2016, 86(2): 1406–1421.

    Google Scholar 

  17. Chen T., Li S. Numerical investigation of guide-plate induced pressure fluctuations on guide vanes of three gorges turbines [J]. Journal of Fluids Engineering, 2011, 133(6): 061101.

    Article  Google Scholar 

  18. Chen T. First step of verification of Liʼs hypothesis: identification of a new vortex structure induced by guide-plate in three gorges turbines [D]. Doctoral Thesis, Coventry, UK: University of Warwick, 2014.

    Google Scholar 

  19. Chen T., Zhang Y., Li S. Instability of large-scale prototype Francis turbines of Three Gorges power station at part load [J]. Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy, 2016, 230(7): 619–632.

    Google Scholar 

  20. Zhang R., Mao F., Wu J. et al. Characteristics and control of the draft-tube flow in part-load Francis turbine [J]. Journal of Fluids Engineering, 2009, 131(2): 021101.

    Article  Google Scholar 

  21. Galván S., Reggio M., Guibault F. Numerical optimization of the inlet velocity profile ingested by the conical draft tube of a hydraulic turbine [J]. Journal of Fluids Engineering, 2015, 137(7): 071102.

    Article  Google Scholar 

  22. Zhang Y., Liu K., Xian H. et al. A review of methods for vortex identification in hydroturbines [J]. Renewable and Sustainable Energy Reviews, 2018, 81(1): 1269–1285.

    Article  Google Scholar 

  23. Jeong J., Hussain F. On the identification of a vortex [J]. Journal of Fluid Mechanics, 1995, 285: 69–94.

    Article  MathSciNet  MATH  Google Scholar 

  24. Zhang Y., Zhang Y., Li S. The secondary Bjerknes force between two gas bubbles under dual-frequency acoustic excitation [J]. Ultrasonics Sonochemistry, 2016, 29: 129–145.

    Article  Google Scholar 

  25. Zhang Y., Zhang Y. Chaotic oscillations of gas bubbles under dual-frequency acoustic excitation [J]. Ultrasonics Sonochemistry, 2018, 40 (Part B): 151–157.

    Article  Google Scholar 

  26. Zhang Y., Zhang Y., Li S. Combination and simultaneous resonances of gas bubbles oscillating in liquids under dual-frequency acoustic excitation [J]. Ultrasonics Sonochemistry, 2017, 35 (Part A): 431–439.

    Article  Google Scholar 

  27. Zhang Y., Gao Y., Guo Z. et al. Effects of mass transfer on damping mechanisms of vapor bubbles oscillating in liquids [J]. Ultrasonics Sonochemistry, 2018, 40 (Part A): 120–127.

    Article  Google Scholar 

  28. Zhang Y., Gao Y., Du X. Stability mechanisms of oscillating vapor bubbles in acoustic fields [J]. Ultrasonics Sonochemistry, 2018, 40 (Part A): 808–814.

    Article  Google Scholar 

  29. Zhang Y., Guo Z., Gao Y. et al. Acoustic wave propagation in bubbly flow with gas, vapor or their mixtures [J]. Ultrasonics Sonochemistry. 2017, 40 (Part B): 40–45.

    Article  Google Scholar 

  30. Zhang Y., Zhang Y., Qian Z. et al. A review of microscopic interactions between cavitation bubbles and particles in silt-laden flow [J]. Renewable and Sustainable Energy Reviews, 2016, 56: 303–318.

    Article  Google Scholar 

  31. Tan L., Yu Z., Xu Y. et al. Role of blade rotational angle on energy performance and pressure fluctuation of a mixed-flow pump [J]. Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy, 2017, 231(3): 227–238.

    Google Scholar 

  32. Tan L., Zhu B., Cao S. et al. Numerical simulation of unsteady cavitation flow in a centrifugal pump at off-design conditions [J]. Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, 2014, 228(11): 1994–2006.

    Google Scholar 

  33. Li J. W., Zhang Y. N., Liu K. H. et al. Numerical simulation of hydraulic force on the impeller of reversible pump turbines in generating mode [J]. Journal of Hydrodynamics, 2017, 29(4): 603–609.

    Article  Google Scholar 

  34. Li D., Wang H., Qin Y. et al. Numerical simulation of hysteresis characteristic in the hump region of a pumpturbine model [J]. Renewable Energy, 2018, 115: 433–447.

    Article  Google Scholar 

  35. Li D., Wang H., Qin Y. et al. Entropy production analysis of hysteresis characteristic of a pump-turbine model [J]. Energy Conversion and Management, 2017, 149: 175–191.

    Article  Google Scholar 

  36. Gao D., Qiu X., Zhang Y. et al. Life cycle analysis of coal based methanol-to-olefins processes in China [J]. Computers and Chemical Engineering, 2018, 109: 112–118.

    Article  Google Scholar 

  37. Gao D., Ye C., Ren X. et al. Life cycle analysis of direct and indirect coal liquefaction for vehicle power in China [J]. Fuel Processing Technology, 2018, 169: 42–49.

    Article  Google Scholar 

Download references

Acknowledgements

This work was suppored by the Fundamental Research Funds for the Central Universities (Grant No. JB2015RCY04), the Open Research Fund Program of Key Laboratory of Fluid and Power Machinery, Ministry of Education, Xihua University (Grant No. szjj-2017-100-1-003), the Open Foundation of National Research Center of Pumps, Jiangsu University (Grant No. NRCP201601) and the Open Research Fund Program of State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University (Grant No. LAPS16014).

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Authors and Affiliations

  1. Key Laboratory of Condition Monitoring and Control for Power Plant Equipment, Ministry of Education, School of Energy, Power and Mechanical Engineering, North China Electric Power University, Beijing, 102206, China

    Ting Chen  (陈婷), Xianghao Zheng  (郑祥豪) & Yu-ning Zhang  (张宇宁)

  2. School of Science, Wuhan Institute of Technology, Wuhan, 430205, China

    Ting Chen  (陈婷)

  3. School of Engineering, University of Warwick, Coventry, CV4 7AL, UK

    Ting Chen  (陈婷) & Shengcai Li

  4. Key Laboratory of Fluid and Power Machinery, Ministry of Education, Xihua University, Sichuan, 610039, China

    Yu-ning Zhang  (张宇宁)

  5. National Research Center of Pumps, Jiangsu University, Zhenjiang, 212013, China

    Yu-ning Zhang  (张宇宁)

Authors
  1. Ting Chen  (陈婷)
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  2. Xianghao Zheng  (郑祥豪)
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  3. Yu-ning Zhang  (张宇宁)
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  4. Shengcai Li
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Corresponding author

Correspondence to Yu-ning Zhang  (张宇宁).

Additional information

Project supported by the National Natural Science Foundation of China (Grant No. 51506051).

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Chen, T., Zheng, X., Zhang, Yn. et al. Influence of upstream disturbance on the draft-tube flow of Francis turbine under part-load conditions. J Hydrodyn 30, 131–139 (2018). https://doi.org/10.1007/s42241-018-0014-9

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  • DOI: https://doi.org/10.1007/s42241-018-0014-9

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