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Journal of Hydrodynamics 2014年第1期26卷 137-143页

作者：彭小东杨朝晖刘善均鞠小明 State Key Laboratory of hydraulics and Mountain River Engineering Sichuan University Department of Water Resources of Guizhou Province

For the metal spiral casing of water turbines, a new equivalent pipe algorithm is developed based on the idea of equiangu-lar spiral. Prototype tests and computations are carried out to investigate the hydraulic transient characteristics. The computation re-sults by using the new model are in a good agreement with the prototype test data with respect to the maximum speed of the tur-bine-generator unit, the maximum water hammer pressure in the spiral casing and the maximum vacuum in the draft tube. The propo-sed method is a significant improvement over the conventional algorithm with the accuracy increased and the error reduced by about 3%.

关键词： equiangular spiral metal spiral casing equivalent pipe hydraulic transient

Flux vector splitting solutions for coupling hydraulic transient of gas-liquid-solid three-phase flow in pipelines

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Applied Mathematics and Mechanics(English Edition) 2013年第7期34卷 811-822页

作者：陈明焦光伟邓松圣王建华 Department of Petroleum Supply Engineering Logistical Engineering University of PLA

The gas-liquid-solid three-phase mixed flow is the most general in multiphase mixed transportation. It is significant to exactly solve the coupling hydraulic transient problems of this type of multiphase mixed flow in pipelines. Presently, the method of characteristics is widely used to solve classical hydraulic transient problems. However, when it is used to solve coupling hydraulic transient problems, excessive interpolation errors may be introduced into the results due to unavoidable multiwave interpolated calculations. To deal with the problem, a finite difference scheme based on the Steger- Warming flux vector splitting is proposed. A flux vector splitting scheme is established for the coupling hydraulic transient model of gas-liquid-solid three-phase mixed flow in the pipelines. The flux subvectors are then discretized by the Lax-Wendroff central difference scheme and the Warming-Beam upwind difference scheme with second-order precision in both time and space. Under the Rankine-Hugoniot conditions and the corresponding boundary conditions, an effective solution to those points located at the boundaries is developed, which can avoid the problem beyond the calculation region directly induced by the second-order discrete technique. Numerical and experimental verifications indicate that the proposed scheme has several desirable advantages including high calculation precision, excellent shock wave capture capability without false numerical oscillation, low sensitivity to the Courant number, and good stability.

关键词： gas-liquid-solid three-phase flow fluid-structure interaction hydraulic transient flux vector splitting second-order precision

THEORETICAL ANALYSIS ON hydraulic transient RESULTED BY SUDDEN INCREASE OF INLET PRESSURE FOR LAMINAR PIPELINE FLOW

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Applied Mathematics and Mechanics(English Edition) 2004年第6期25卷 672-678页

作者：邓松圣周绍骑廖振方邱正阳曾顺鹏 Department of Oil Supply Engineering Chongqing College of Logistic EngineeringChongqing 400016P.R.China Mechanical College Chongqing UniversityChongqing 400044P.R.ChinaDepartment of Oil Supply EngineeringChongqing College of Logistic EngineeringChongqing 400016P.R.China Mechanical College Chongqing UniversityChongqing 400044P.R.China

hydraulic transient, which is resulted from sudden increase of inlet pressure for laminar pipeline flow, is studied. The partial differential equation, initial and boundary conditions for transient pressure were constructed, and the theoretical solution was obtained by variable-separation method. The partial differential equation, initial and boundary conditions for flow rate were obtained in accordance with the constraint correlation between flow rate and pressure while the transient flow rate distribution was also solved by variable-separation method. The theoretical solution conforms to numerical solution obtained by method of characteristics (MOC) very well.

关键词： laminar flow pipeline flow hydraulic transient theoretical solution

ANALYSIS OF FIRST transient PRESSURE OSCILLATION FOR LEAKDETECTION IN A SINGLE PIPELINE

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Journal of Hydrodynamics 2012年第3期24卷 363-370页

作者： YANG Kai-lin LI Fu-tian WANG Tao FU hui State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of WaterResources and Hydropower Research Beijing 100038 China

The leak detection is of great importance in the reliable operation and management of a pipeline system. Recently, attention is shifted to the use of the time domain or frequency domain methods based on the transient analysis. These methods sometimes require accurate pressure signals obtained during the transient period or by creating ideal conditions in testing. This paper proposes a method that does not require transient simulations over the whole or an extended period of time, but uses the first transient pressure oscillation to detect leaks. The method considers the propagation of the pressure oscillation wave created from a fast valve closure and the reflected damp wave from the leak. A leak in the pipe gives rise to reflected waves which in turn create discontinuities in the observed signal at the measurement section. The timing of the reflected damp wave and the magnitude represent the location and the size of the leak, respectively. An analytical expression is derived based on the Method Of Characteristic （MOC） for the relationship between the leakage and the reflected magnitude. The leak detection procedure based on the method is also given. Then the reliability of the method is tested on numerically simulated pressure signals and experimental pressure signals with calibrated leak parameters, and the results indicate a successful application and the promising features of the method.

关键词： leak detection hydraulic transient pressure oscillation pipeline

transient simulation and analysis of the simultaneous load rejection process in pumped storage power stations using a 1-D-3-D coupling method

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Journal of Hydrodynamics 2021年第5期33卷 979-991页

作者： Cheng-cheng Yin Wei Zeng Jian-dong Yang State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China School of Civil Environmental and Mining EngineeringThe University of AdelaideAdelaideAustralia

The load rejection imposes a danger in the pumped storage hydropower plants(PSPs),especially when two or more pump turbines reject their loads *** this paper,the simultaneous load rejection scenarios in the PSPs are simulated and analyzed by using a 1-D,3-D coupling *** PSP pipe system is modeled by using the 1-D method of characteristics(MOC)and one pump turbine is modeled by using the 3-D computational fluid dynamics(CFD).The simulated flow and head are transmitted between the 1-D,3-D regions through the interfaces between these two *** assuming that the installed pump turbines are of the same type and the corresponding branch pipes have the same properties,the variations of the transient pressures and the flowrates in different pump turbines will be ***,only one pump turbine is modeled by the CFD in this study.A new branching junction boundary is proposed to assign the simulated dynamic pressures and flowrates obtained by the 3-D model to other pump *** 1-D-3-D coupling method is validated by experiments with only one pump turbine rejecting its *** simultaneous load rejection of two pump turbines is then simulated and validated by comparing the results with those of the 1-D *** building only one pump turbine 3-D model,a large amount of computational resources can be *** simultaneous load rejection scenario is then analyzed and compared with the single load rejection *** water hammer pressures and a larger rotational speed occur in the simultaneous load rejection scenario,which leads to larger pressure pulsations in the pump *** larger pressure pulsations can be further explained by the flow patterns in the runner channels,in which heavier flow separations and vortexes can be observed in the simultaneous load rejection scenario.

关键词： Pump-turbine,pumped hydro computational fluid dynamics(CFD) hydraulic transient load rejection

DOUBLE METHOD OF CHARACTERISTICS TO ANALYZE hydraulic-THERMAL transientS OF PIPELINE FLOW

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Applied Mathematics and Mechanics(English Edition) 2002年第6期23卷 703-711页

作者：邓松圣周明来蒲家宁 Department of Petroleum Supply Engineering Chongqing College of Logistic Engineering Chongqing P R China

The hydraulic and thermal transients in pipeline flow were studied. The method of characteristics for hydraulic transient analysis of batch transport of pipeline flow had been improved. The thermal transient equation, in which the term with v 3 was involved, had been inferred, while the corresponding method of characteristics was constructed. The double method of characteristics, which can be used to study the coherent hydraulic-thermal transients of batch transport of pipeline flow, was developed.

关键词： pipeline flow thermal transient hydraulic transient method of characteristics