Transient Pressure Measurements on a High Head Model Francis Turbine During Emergency Shutdown, Total Load Rejection, and Runaway

Chirag Trivedi1,2, Michel J. Cervantes3,4, Bhupendra K. Gandhi5, Ole Gunnar Dahlhaug6
1Indian Institute of Technology Roorkee, Roorkee, Uttarakhand 247667, India
2Luleå University of Technology, Luleå SE-971 87, Sweden e-mail:
3Norwegian University of Science and Technology, Trondheim 7491, Norway e-mail:
4Professor Luleå University of Technology, Luleå SE-971 87, Sweden;
5Mem. ASME Professor Indian Institute of Technology Roorkee, Roorkee, Uttarakhand 247667, India e-mail:
6Professor Norwegian University of Science and Technology, Trondheim 7491, Norway e-mail:

Tóm tắt

The penetration of intermittent wind and solar power to the grid network above manageable limits disrupts electrical power grids. Consequently, hydraulic turbines synchronized to the grid experience total load rejection and are forced to shut down immediately. The turbine runner accelerates to runaway speeds in a few seconds, inducing high-amplitude, unsteady pressure loading on the blades. This sometimes results in a failure of the turbine components. Moreover, the unsteady pressure loading significantly affects the operating life of the turbine runner. Transient measurements were carried out on a scale model of a Francis turbine prototype (specific speed = 0.27) during an emergency shutdown with a transition into total load rejection. A detailed analysis of variables such as the head, discharge, pressure at different locations including the runner blades, shaft torque, and the guide vane angular movements are performed. The maximum amplitudes of the unsteady pressure fluctuations in the turbine were observed under a runaway condition. The amplitudes were 2.1 and 2.6 times that of the pressure loading at the best efficiency point in the vaneless space and runner, respectively. Such high-amplitude, unsteady pressure pulsations can affect the operating life of the turbine.

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Tài liệu tham khảo

2013, Effect of Transients on Francis Turbine Runner Life: A Review, J. Hydraulic Res., 51, 121, 10.1080/00221686.2012.732971

2011, The Impact of Hydroelectric Power and Other Forms of Generation on Grid Frequency Stability for the WECC Region

2013, Pressure Measurements on a High Head Francis Turbine During Load Acceptance and Rejection, J. Hydraulic Res., 52, 1

2014, Experimental Investigations of Transient Pressure Variations in a High Head Model Francis Turbine During Start-Up and Shutdown, J. Hydrodyn. Ser. B, 26, 277, 10.1016/S1001-6058(14)60031-7

Deschênes, C., Fraser, R., and Fau, J.-P., 2002, “New Trends in Turbine Modelling and New Ways of Partnership,” International Conference on Hydraulic Efficiency Measurement—IGHEM, Toronto, Ontario, Canada, July 17–19, pp. 1–12.

Huth, H.-J., 2005, “Fatigue Design of Hydraulic Turbine Runners,” Ph.D. thesis. Norwegian University of Science and Technology, NTNU, Trondheim, Norway.

Nicolet, C., 2007, “Hydroacoustic Modelling and Numerical Simulation of Unsteady Operation of Hydroelectric Systems,” Ph.D. thesis, No. 3751, École Polytechnique Fédérale de Lausanne (EPFL), Switzerland.

2010, Runaway Transient Simulation of a Model Kaplan Turbine, IOP Conf. Ser.: Earth Environ. Sci., 12, 012073

2006, Simulation of Unsteady Flow and Runner Rotation During Shut-Down of an Axial Water Turbine, J. Hydraulic Res., 44, 129, 10.1080/00221686.2006.9521668

2003, Transient Problems During Load Rejection

2011, Parametric Study of Water Column Separation in Francis Pump-Turbine Draft Tube

Pejovic, S., Karney, B., and Zhang, Q., 2004, “Water Column Separation in Long Tailrace Tunnel,” Hydroturbo 2004, International Conference on Hydro-Power Engineering, Brno, Czech Republic, Oct. 18–22.

2001, Dynamic Orifice Model on Water Hammer Analysis of High or Medium Heads of Small Hydro Power Schemes, J. Hydraul. Res., 39, 429, 10.1080/00221680109499847

2012, Stability Limits of Reversible-Pump Turbines in Turbine Mode of Operation and Measurements of Unstable Characteristics, ASME J. Fluids Eng., 134, 111202, 10.1115/1.4007589

2011, Experimental Evidence of Rotating Stall in a Pump-Turbine at Off-Design Conditions in Generating Mode, ASME J. Fluids Eng., 133, 051104, 10.1115/1.4004088

Gagnon, M., and Leonard, F., 2013, “Transient Response and Life Assessment: Case Studies on the Load Rejection of Two Hydroelectric Turbines,” Surveillance 7, International Conference, Institute of Technology of Chartres, France, Oct. 29–30.

2011, Unstable Characteristics and Rotating Stall in Turbine Brake Operation of Pump-Turbines, ASME J. Fluids Eng., 133, 041101, 10.1115/1.4003874

2010, A Review on Oscillatory Problems in Francis Turbine, 217

Gagnon, M., Tahan, S. A., Bocher, P., and Thibault, D., 2010, “Impact of Startup Scheme on Francis Runner Life Expectancy,” IOP Conf. Ser.: Earth Environ. Sci., 12(1), p. 012107.

Nicolle, J.-F. M., and Giroux, A.-M., 2012, “Transient CFD Simulation of a Francis Turbine Startup,” 26th IAHR Symposium on Hydraulic Machinery and Systems, Beijing, China, Aug. 19–23.

1982, Transient Characteristics of a Centrifugal Pump During Starting Period, ASME J. Fluids Eng., 104, 6, 10.1115/1.3240859

1986, Transient Characteristics of a Centrifugal Pump During Stopping Period, ASME J. Fluids Eng., 108, 392, 10.1115/1.3242594

2007, Transient Behavior of Turbomachineries: Applications to Radial Flow Pump Startups, ASME J. Fluids Eng., 129, 1436, 10.1115/1.2776963

2007, Frequencies in the Vibration Induced by the Rotor Stator Interaction in a Centrifugal Pump Turbine, ASME J. Fluids Eng., 129, 1428, 10.1115/1.2786489

2009, Experimental Evidence of Hydroacoustic Pressure Waves in a Francis Turbine Elbow Draft Tube for Low Discharge Conditions, ASME J. Fluids Eng., 131, 081102, 10.1115/1.3155944

2012, Unsteady Pressure Analysis of Swirling Flow With Vortex Rope and Axial Water Injection in a Discharge Cone, ASME J. Fluids Eng., 134, 081104, 10.1115/1.4007074

1997, Hydro Unit Start-Up Costs and Their Impact on the Short Term Scheduling Strategies of Swedish Power Producers, IEEE Trans. Power Syst., 12, 38, 10.1109/59.574921

Bakken, B. H., and Bjørkvoll, T., 2002, “Hydropower Unit Start-Up Costs,” Power Engineering Society Summer Meeting, Chicago, IL, July 25. pp. 1522–1527.

2008, Thirty Years of Numerical Flow Simulation in Hydraulic Turbomachines, Acta Mech., 201, 211, 10.1007/s00707-008-0060-4

Hutton, S. P., 1954, “Component Losses in Kaplan Turbines and the Prediction of Efficiency From Model Tests,” Proc. of the Institution of Mechanical Engineers, pp. 168–743.

1978, Efficiency Scale-Up for Hydraulic Turbo-Machines With Due Consideration of Surface Roughness, J. Hydraul. Res., 16, 55, 10.1080/00221687809499632

1989, Analysis of Scale Effects on Performance Characteristics of Hydraulic Turbines, J. Hydraul. Res., 27, 809, 10.1080/00221688909499109

Dorfler, P. K., 2009, “Evaluating 1D Models for Vortex-Induced Pulsation in Francis Turbines,” 3rd IAHR International Meeting of the Workgroup on Cavitation and Dynamic Problems in Hydraulic Machinery and Systems, Brno, Czech Republic, Oct. 14–16.

2010, Francis Full-Load Surge Mechanism Identified by Unsteady 2-Phase CFD, IOP Conf. Series: Earth Environ. Sci., 12, 012026

2010, Prediction of a Francis Turbine Prototype Full Load Instability From Investigations on the Reduced Scale Model, IOP Conf. Series: Earth Environ. Sci., 12, 012025

Hydraulic Turbines, Storage Pumps and Pump-Turbines—Model Acceptance Tests

2013, Flow-Induced Pulsation and Vibration in Hydroelectric Machinery, 1st ed.

Hasmatuchi, V., 2012, “Hydrodynamics of a Pump-Turbine Operating at Off-Design Conditions in Generating Mode,” Ph.D. thesis, No. 5373, École Polytechnique Fédérale De Lausanne, Switzerland.

Jacob, T., 1993, “Evaluation sur Modele Reduit et Prediction la Stabilite de Fonctionnement des Turbines Francis,” Ph.D. thesis, No. 1146, Departement de Mecanique, Ecole Polytechnique Federale de Lausanne, Lausanne, Switzerland.

2013, Experimental and Numerical Studies for a High Head Francis Turbine at Several Operating Points, ASME J. Fluids Eng., 135, 111102, 10.1115/1.4024805

Field Acceptance Tests to Determine the Hydraulic Performance of Hydraulic Turbines, Storage Pumps and Pump-Turbines

Guide for Commissioning, Operation and Maintenance of Hydraulic Turbines

Hydraulic Turbines-Testing of Control Systems

Guide to Specification of Hydraulic Turbine Control Systems

Guide for Field Measurement of Vibrations and Pulsations in Hydraulic Machines (Turbines, Storage Pumps and Pump-Turbines)

Hydraulic Turbines and Pump-Turbines, Performance Test Codes

2007, Experimental Study and Numerical Simulation of the FLINDT Draft Tube Rotating Vortex, ASME J. Fluids Eng., 129, 146, 10.1115/1.2409332

1962, Theory of the Vortex Breakdown Phenomenon, J. Fluid Mech., 14, 593, 10.1017/S0022112062001482