Research Papers: Flows in Complex Systems

Francis-Type Reversible Turbine Field Investigation During Fast Closure of Wicket Gates

[+] Author and Article Information
Mao Xiuli

College of Water Resources and Architectural
Northwest Agriculture and Forestry University,
Weihui Road 23,
Yangling District,
Xianyang City 712100, Shanxi Province, China
e-mail: 140402030002@hhu.edu.cn

Pavesi Giorgio

Department Industrial Engineering,
University of Padova,
Via Venezia 1,
Padova 35131, Italy
e-mail: giorgio.pavesi@unipd.it

Zheng Yuan

National Engineering Research Center of Water
Resources Efficient Utilization and Engineering
Hohai University,
Xikang Road 1,
Nanjing 210098, China
e-mail: zhengyuan@hhu.edu.cn

1Corresponding author.

Contributed by the Fluids Engineering Division of ASME for publication in the JOURNAL OF FLUIDS ENGINEERING. Manuscript received June 29, 2017; final manuscript received January 17, 2018; published online February 16, 2018. Assoc. Editor: Riccardo Mereu.

J. Fluids Eng 140(6), 061103 (Feb 16, 2018) (10 pages) Paper No: FE-17-1394; doi: 10.1115/1.4039089 History: Received June 29, 2017; Revised January 17, 2018

Flexible electricity demand and variability of the electricity produced by wind turbines and photovoltaic affect the stable operations of power grids. Pump-turbines are used to stabilize the power grid by maintaining a real-time electricity demand. Consistently, the machines experience transient conditions during the course of operation, such as start-up, load acceptance, load rejection, and shutdown, which induce high amplitude pressure pulsations and affect operating lifespan of the components. During the closure of the wicket gates, the transient flow characteristics is analyzed for a Francis-type reversible pump-turbine in generating mode by three-dimensional (3D) numerical simulation with a moving mesh technique and using detached eddy simulation (DES) turbulent model. Mesh motion is carried out in the region of wicket gates during the load rejection by a moving, sliding mesh, which makes dynamic flow simulation available, instead of building various steady models with different guide vanes angles. The transient flow characteristics are illustrated by analyzing the flow, torque, and pressure fluctuations signals by frequency and time–frequency analyses. The flow field analysis includes the onset and strengthening of unsteady phenomena during the turbine load reduction. The flow pattern in return channel maintained a quite stable flow field, whereas the flow pattern in the runner and draft tube emphasized its instability with the flow rate decreased. Influence of 3D unsteady flow structures on runner is determined, and its evolution is characterized spectrally during fast closure of wicket gates.

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Caralis, G. , Papantonis, D. , and Zervos, A. , 2012, “ The Role of Pumped Storage Systems Towards the Large Scale Wind Integration in the Greek Power Supply System,” Renewable Sustainable Energy Rev., 16(5), pp. 2558–2565. [CrossRef]
Pérez-Díaz, J. I. , Cavazzini, G. , Blázquez, F. , Platero, C. , Fraile-Ardanuy, J. , Sánchez, J. A. , and Chazarra, M. , 2014, “ Technological Developments for Pumped-Hydro Energy Storage,” Mechanical Storage Subprogramme, Joint Programme on Energy Storage, European Energy Research Alliance, Brussels, Belgium, Technical Report. https://www.eera-set.eu/wp-content/uploads/Technological-Developments-for-Pumped-Hydro-Energy-Storage_EERA-report-2014.pdf
Taulan, J. P. , Laurier, P. , Bourrilhon, M. , and Bornard, L. , 2009, “ Pump-Turbine Integration in Renewable Energy Systems,” Waterpower XVI Conference, Spokane, WA, July 27–30, Paper No. 114.
Brauner, G. , 2012, “ Wege Zur Nachhaltigen Energieversorgung—Herausforderung an Speicher Und Thermische Kraftwerke (Path to Renewable Energy Supply—Challenge for Energy Storage and Thermal Power Stations),” 12th Symposium Energy Innovations, Graz, Austria, Mar. 15–17, pp. 1–9.
VDE Study, 2012, “ Flexibilization of Power Generation for Renewable Energy Systems (Erneuerbare Energie Braucht Flexible Kraftwerke—Szenarien bis 2020),” ETG-Task Force Flexibilisierung des Kraftwerksparks, Frankfurt, Germany.
SEC 85/3, 2008, “ Package of Implementation Measures for the EU's Objective on Climate Change and Renewable Energy for 2020,” Commission of the European Communities, Brussels, Belgium, Report No. SEC 85-3. http://ec.europa.eu/transparency/regdoc/rep/2/2008/EN/2-2008-85-EN-1-0.Pdf
Beurskens, L. M. W. , and Hekkenberg, M. , 2011, “ Renewable Energy Projections as Published in the National Renewable Energy Action Plans of the European Member States,” European Environment Agency, Copenhagen, Denmark, Report No. ECN-E-10-069. https://www.ecn.nl/docs/library/report/2010/e10069.pdf
Ardizzon, G. , Cavazzini, G. , and Pavesi, G. , 2014, “ A New Generation of Small Hydro and Pumped-Hydro Power Plants: Advances and Future Challenges,” Renewable Sustainable Energy Rev., 31, pp. 746–761. [CrossRef]
Pavesi, G. , Cavazzini, G. , and Ardizzon, G. , 2016, “ Numerical Analysis of the Transient Behaviour of a Variable Speed Pump-Turbine During a Pumping Power Reduction Scenario,” Energies, 9(7), pp. 534–544. [CrossRef]
Nilsson, O. , and Sjelvgren, D. , 1997, “ Hydro Unit Start-Up Costs and Their Impact on the Short Term Scheduling Strategies of Swedish Power Producers,” IEEE Trans. Power Syst., 12(1), pp. 38–44. [CrossRef]
Nicolle, J. , Giroux, A. M. , and Morissette, J. F. , 2014, “ CFD Configurations for Hydraulic Turbine Startup,” 27th IAHR Symposium Hydraulic Machinery and Systems, Montreal, QC, Canada, Sept. 22–26, p. 032021.
Gagnon, M. , Jobidon, N. , Lawrence, M. , and Larouche, D. , 2014, “ Optimization of Turbine Startup: Some Experimental Results From a Propeller Runner,” 27th IAHR Symposium Hydraulic Machinery and Systems, Montreal, QC, Canada, Sept. 22–26, p. 032022.
Amiri, K. , Mulu, B. , Raisee, M. , and Cervantes, M. J. , 2014, “ Load Variation Effects on the Pressure Fluctuations Exerted on a Kaplan Turbine Runner,” 27th IAHR Symposium Hydraulic Machinery and Systems, Montreal, QC, Canada, Sept. 22–26, p. 032005.
Trivedi, C. , Cervantes, M. , Dahlhaug, O. , and Gandhi, B. , 2015, “ Experimental Investigation of a High Head Francis Turbine During Spin-No-Load Operation,” ASME J. Fluids Eng., 137(6), p. 061106. [CrossRef]
Trivedi, C. , Cervantes, M. , Gandhi, B. , and Dahlhaug, O. , 2014, “ Transient Pressure Measurements on a High Head Model Francis Turbine During Emergency Shutdown, Total Load Rejection, and Runaway,” ASME J. Fluids Eng., 136(12), p. 121107.
Trivedi, C. , Cervantes, M. J. , and Gandhi, B. , and Dahlhaug, O. , 2014, “ Pressure Measurements on a High-Head Francis Turbine During Load Acceptance and Rejection,” J. Hydraul. Res., 52(2), pp. 283–297. [CrossRef]
Trivedi, C. , Cervantes, M. J. , and Gandhi, B. K. , 2016, “ Numerical Investigation and Validation of a Francis Turbine at Runaway Operating Conditions,” Energ., 9(3), p. 22.
Trivedi, C. , Gandhi, B. , and Cervantes, M. , 2013, “ Effect of Transients on Francis Turbine Runner Life: A Review,” J. Hydraul. Res., 51(2), pp. 121–132. [CrossRef]
Kolšek, T. , Duhovnik, J. , and Bergant, A. , 2006, “ Simulation of Unsteady Flow and Runner Rotation During Shut-Down of an Axial Water Turbine,” J. Hydraul. Res., 44(1), pp. 129–137. [CrossRef]
Melot, M. , Monette, C. , Coutu, A. , and Nenneman, B. , 2013, “ Speed No-Load Operating Condition: A New Standard Francis Runner Design Procedure to Predict Static Stresses,” XVIII Conference on Hydraulics, Water Resources, Coastal and Environmental Engineering, Innsbruck, Austria, Dec. 4–6, pp. 1–8.
Côté, P. , Dumas, G. , Moisan, E. , and Boutet-Blais, G. , 2014, “ Numerical Investigation of the Flow Behavior Into a Francis Runner During Load Rejection,” 27th IAHR Symposium Hydraulic Machinery and Systems, Montreal, QC, Canada, Sept. 22–26, p. 032023.
Xiao, J. L. , Zhu, E. Q. , and Wang, G. D. , 2012, “ Numerical Simulation of Emergency Shutdown Process of Ring Gate in Hydraulic Turbine Runaway,” ASME J. Fluids Eng., 134(12), p. 124501. [CrossRef]
Trivedi, C. , Gandhi, B. , Cervantes, M. , and Dahlhaug, O. , 2015, “ Experimental Investigations of a Model Francis Turbine During Shutdown at Synchronous Speed,” Renewable Energy, 83, pp. 828–836. [CrossRef]
Kuwabara, T. , Katayama, K. , Nakagawa, H. , and Hagiwara, H. , 2000, “ Improvements of Transient Performance of Pump Turbine Upon Load Rejection,” Power Engineering Society Summer Meeting (PESS), Seattle, WA, July 16–20, pp. 1783–1788.
Trivedi, C. , Cervantes, M. , Gandhi, B. , and Dahlhaug, O. , 2014, “ Experimental Investigations of Transient Pressure Variations in a High Head Model Francis Turbine During Start-Up and Shutdown,” J. Hydrodyn., 26(2), pp. 277–290. [CrossRef]
Nicolet, C. , Alligné, S. , Kawkabani, B. , Koutnik , J. , Simond, J.-J. , and Avellan, F. , 2009, “ Stability Study of Francis Pump-Turbine at Runaway,” Third Meeting IAHR Workgroup on Cavitation and Dynamic Problems in Hydraulic Machinery and Systems, Brno, Czech Republic, Oct. 14–16, Paper No. EPFL-CONF-163857. http://www.powervision-eng.ch/Simsen_hydro/Publications/pdf/IAHR_WG1_2009_1.pdf
Yin, J. L. , Wang, D. Z. , Wei, X. Z. , and Wang, L. Q. , 2013, “ Hydraulic Improvement to Eliminate S-Shaped Curve in Pump Turbine,” ASME J. Fluids Eng., 135(7), p. 071105. [CrossRef]
Zeng, W. , Yang, J. , and Guo, W. , 2015, “ Runaway Instability of Pump-Turbines in S-Shaped Regions Considering Water Compressibility,” ASME J. Fluids Eng., 137(5), p. 051401. [CrossRef]
Yao, Z. , Bi, H. L. , Huang, Q. S. , Li, Z. J. , and Wang, Z. W. , 2013, “ Analysis on Influence of Wicket Gates Closure Laws of Pump-Turbine on Load Rejection Transient Process,” IOP Sixth International Conference on Pumps and Fans With Compressors and Wind (ICPF), Beijing, China, Sept. 19–22, pp. 66–71.
Yang, J. , Pavesi, G. , Yuan, S. , Cavazzini, G. , and Ardizzon, G. , 2015, “ Experimental Characterization of a Pump–Turbine in Pump Mode at Hump Instability Region,” ASME J. Fluids Eng., 137(5), p. 051109.
Cavazzini, G. , Pavesi, G. , and Ardizzon, G. , 2011, “ Pressure Instabilities in a Vaned Centrifugal Pump,” Proc. Inst. Mech. Eng., Part A, 225(7), pp. 930–939. [CrossRef]
Cavazzini, G. , Covi, A. , Pavesi, G. , and Ardizzon, G. , 2016, “ Analysis of the Unstable Behavior of a Pump-Turbine in Turbine Mode: Fluid-Dynamical and Spectral Characterization of the S-Shape Characteristic,” ASME J. Fluids Eng., 138(2), p. 021105. [CrossRef]
Menter, F. R. , and Kuntz, M. , 2003, “ Development and Application of a Zonal DES Turbulence Model for CFX-5—CFX-Validation Report,” ANSYS, Canonsburg, PA, Report No. CFX-VAL17/0503.
Yan, J. , Koutnik, J. , Seidel, U. , and Hübner, B. , 2010, “ Compressible Simulation of Rotor-Stator Interaction in Pump-Turbines,” Int. J. Fluid Mach. Syst., 3(4), pp. 315–323.
Yin, J. L. , Wang, D. Z. , Wang, L. Q. , Wu, Y. L. , and Wei, X. Z. , 2010, “ Effects of Water Compressibility on the Pressure Fluctuation Prediction in Pump Turbine,” IOP Conf. Ser.: Earth Environ. Sci., 15(6), p. 062030.
Kurzin, V. B. , 2013, “ Effect of Water Compressibility on Nonstationary Characteristics of Hydraulic Turbines,” J. Eng. Phys. Thermophys., 86(5), pp. 1202–1209. [CrossRef]
Xiaoqin, L. , Jinshi, C. , and Peng, C. , 2013, “ Wicket Gate Closure Control Law to Improve the Transient of a Water Turbine,” Adv. Mater. Res., 732–733, pp. 451–456.
Cui, H. C. , Fan, H. G. , and Chen, N. X. , 2012, “ Optimization of Wicket-Gate Closing Law Considering Different Cases,” IOP Conf. Ser.: Earth Environ. Sci., 15(5), p. 052008.
Cuzmoş, A. , Câmpian, C. V. , Frunzăverde, D. , Dumbravă, C. , and Budai, A. M. , 2015, “ Tests Performed on Hydraulic Turbines at Commissioning or After Capital Repair—Part I: Tests Performanced on a 78-MW Francis Turbine,” Analele Universităţii “Eftimie Murgu” Fascicula de Inginerie ANUL XXII, Vol. 1, pp. 1453–7397.


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Fig. 1

3D scheme of the model configuration: (a) face-to-face configuration (γ = 0 deg) and (b) wicket gates γ = 8 deg out of alignment

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Fig. 2

Meridional view of the numerical model: regions filled in gray refer to the blades; regions filled in black refer to the leakage system. (1) Runner outlet, (2) runner inlet, (3) trailing edge wicket gate, (4) leading edge wicket gate, (5) trailing edge return channel, and (6) leading edge return channel.

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Fig. 3

Details of the coarse mesh of the numerical model: (a) runner and wicket gates, (b) wicket gate and return channel trailing edge, and (c) return channel leading edge

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Fig. 4

Grid sensitivity analysis

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Fig. 5

Scenario of load rejection of pump turbine at turbine mode: (a) the closure law of wicket gate and (b) position of wicket vane at maximum (α = 23.44 deg) and minimum (α = 5.79 deg)

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Fig. 6

Distribution of mesh angle of wicket gate at different positions: (a) α = 23.44 deg and (b) α = 5.79 deg. Details at the region where adjacent blades are close to each other: (c) mesh angle and (d) edge length ratio.

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Fig. 7

Comparison between numerical and experimental performance curves

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Fig. 8

Flow rate and power in the turbine

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Fig. 9

Flow rate variations acquired: (a) in three consecutive return channels and (b) overview flow rate evolution in all return channels

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Fig. 10

Flow rate variations acquired: (a) in two consecutive wicket gates and (b) overview of flow rate development in all wicket gates

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Fig. 11

Flow field in return channels and the diffuser channels: (a) percentage closure = 0.0%, (b) percentage closure = 44.2%, (c) percentage closure = 58.9%, (d) percentage closure = 69.9%, (e) percentage closure = 84.6%, and (f) percentage closure = 95.7%

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Fig. 12

Power-spectra of the normalized flow rate acquired intwo consecutive return channels

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Fig. 13

Power-spectra of the normalized flow rate acquired in a wicket gate

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Fig. 14

Sketch of the tested configuration (γ = 8 deg) with the distribution of monitoring points. D1–D12 at midspan on the wicket gate; R1–R19 at midspan on the blade of return channel; points with IP on the runner blade: IP01–IP08 are close to runner shroud, IP11–IP18 are in the middle line and IP21–IP28 are close to runner hub.

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Fig. 15

Power-spectra of the pressure coefficient acquired at: (a) trailing edge (point D1 in Fig. 14) and (b) leading edge (point D5 in Fig. 14) of a wicket gate

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Fig. 16

Power-spectra of the dimensionless torque factor TED evaluated on the pin of the wicket gates

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Fig. 17

Pressure and streamlines in the runner: (a) Time/TimeMax = 0.14—percentage closure = 1.2%, (b) Time/TimeMax = 0.42—percentage closure = 33.1%, (c) Time/TimeMax = 0.56—percentage closure = 51.5%, (d) Time/TimeMax = 0.72—percentage closure = 73.6%, (e) Time/TimeMax = 0.81—percentage closure = 84.6%, and (f) Time/TimeMax = 0.86—percentage closure = 90.8%

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Fig. 18

Power-spectra of the pressure factor p/ρ/U2: (a) pressure side IP01, (b) suction side IP01, (c) pressure side IP05, (d) suction side IP05, (e) pressure side IP28, and (f) suction side IP28



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