Numerical Simulation Study on Hydraulic Transients in Hydropower Station with Trigeminy Surge Tank

A numerical model of fluid transients in long corridor surge tank, based on the equations of Saint-Venant, is developed. The implicit method of Preissman, with appropriate boundary conditions, is used to solve these two nonlinear partial differential equations. The hydraulic transients with new model and normal surge tank model are simulated and compared with model experiments. It is clarified that the new numerical model can simulate the changes of water level in long corridor surge tank and pressure along penstock realistically. The new model provides scientific basis for studying hydraulic transients of hydropower station with long corridor surge tank.

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Hydraulic Transients in the Long Diversion-Type Hydropower Station with a Complex Differential Surge Tank

The Scientific World JOURNAL ◽

10.1155/2014/241868 ◽

2014 ◽

Vol 2014 ◽

pp. 1-11 ◽

Cited By ~ 10

Author(s):

Xiaodong Yu ◽

Jian Zhang ◽

Ling Zhou

Keyword(s):

Pressure Difference ◽

Mathematic Model ◽

Hydropower Station ◽

Maximum Pressure ◽

Surge Tank ◽

Hydraulic Transients ◽

Rotating Speed ◽

Spiral Case ◽

Two Sides ◽

Breast Wall

Based on the theory of hydraulic transients and the method of characteristics (MOC), a mathematic model of the differential surge tank with pressure-reduction orifices (PROs) and overflow weirs for transient calculation is proposed. The numerical model of hydraulic transients is established using the data of a practical hydropower station; and the probable transients are simulated. The results show that successive load rejection is critical for calculating the maximum pressure in spiral case and the maximum rotating speed of runner when the bifurcated pipe is converging under the surge tank in a diversion-type hydropower station; the pressure difference between two sides of breast wall is large during transient conditions, and it would be more serious when simultaneous load rejections happen after load acceptance; the reasonable arrangement of PROs on breast wall can effectively decrease the pressure difference.

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Numerical simulation of hydraulic transients in hydropower station with complicated water conveyance system

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/774/1/012142 ◽

2021 ◽

Vol 774 (1) ◽

pp. 012142

Author(s):

Gaohui Li ◽

Shunyi Chen ◽

Jiang Dai ◽

Tianchi Zhou ◽

Lin Zhang

Keyword(s):

Numerical Simulation ◽

Hydropower Station ◽

Hydraulic Transients ◽

Water Conveyance

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Critical superposition instant of surge waves in surge tank with long headrace tunnel

Canadian Journal of Civil Engineering ◽

10.1139/l11-004 ◽

2011 ◽

Vol 38 (3) ◽

pp. 331-337 ◽

Cited By ~ 11

Author(s):

XiaoDong Yu ◽

Jian Zhang ◽

Arash Hazrati

Keyword(s):

Numerical Simulation ◽

Flow Rate ◽

Analytical Formula ◽

Hydropower Station ◽

Surge Tank ◽

Initial Water ◽

Initial Flow ◽

Headrace Tunnel ◽

Fundamental Equations ◽

Computational Basis

Superposed mass oscillation that often occurs in a throttled surge tank with a long headrace tunnel is studied. The instant of the worst superposition of mass oscillation in a surge tank is analysed. The analytical formula predicting the worst superposition instant is derived exactly and verified (1) with a numerical solution to the fundamental equations for the surge tank and (2) with a numerical simulation of hydraulic transients in an actual hydropower station. It is shown that the superposed oscillation provides the highest upsurge at the instant that the initial flow rate in the headrace tunnel and initial water level in the surge tank satisfy the judgement formula. The conclusion provides a theoretical and computational basis for the numerical simulation of maximum upsurge in a surge tank.

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Influence of Successive Load Rejections on Water Hammer Pressure of Spiral Case in Long Diversion-Type Hydropower Station

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.607.551 ◽

2014 ◽

Vol 607 ◽

pp. 551-555 ◽

Cited By ~ 3

Author(s):

Xiao Dong Yu ◽

Jian Zhang ◽

Cheng Yu Fan

Keyword(s):

Numerical Model ◽

Method Of Characteristics ◽

Water Hammer ◽

Hydropower Station ◽

Maximum Pressure ◽

Surge Tank ◽

Hydraulic Transients ◽

Rotating Speed ◽

Spiral Case

Based on the theory of hydraulic transients and method of characteristics (MOC), the numerical model of hydraulic transients in water way system was established using the data of a practical hydropower station, and the probable transients were simulated. The influence of successive load rejection conditions on water hammer pressure of spiral case was analyzed. Compared with simultaneous load rejection, successive load rejection can make maximum pressure in spiral case and maximum rotating speed of runner more serious if the bifurcated pipe converging under surge tank in diversion-type hydropower station.

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