Investigation of Pumped Storage Hydropower Power-Off Transient Process Using 3D Numerical Simulation Based on SP-VOF Hybrid Model

Zhou, Daqing; Chen, Huixiang; Zhang, Languo

doi:10.3390/en11041020

Cited by 36 publications

(14 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Based on a turbine fuzzy model, Nagode and Skrjanc [14] proposed an internal control model of a power turbine, which turns out to show an improvement compared to previous methods. Recently, Zhou [15] confirmed a 3D SP-VOF hybrid simulation to be effective by simulating a power-off process in hydropower pumped storage.…”

Section: Introductionmentioning

confidence: 98%

Investigation of Water Hammer Protection in Water Supply Pipeline Systems Using an Intelligent Self-Controlled Surge Tank

Wan

Zhang

2018

Energies

View full text Add to dashboard Cite

Abstract:A surge tank is a common pressure control device in long pressurized pipelines. The performance is greatly influenced by the location, cross area, and the characteristics of the connector. In order to improve the property of the surge tank, the effect of the connector is numerically analyzed by the method of characteristics (MOC). A hysteretic effect can occur when the discharge capacity is limited. Therefore, the performance of the surge tank can be improved if the discharge capacity of the connector is appropriately controlled according to the different conditions. For the adjustability of the connector's discharge capacity, a kind of intelligent self-controlled surge tank (IST) is proposed. In addition, through simulations and analysis, IST is proved to have advantages in pressure control and applicability compared to normal surge tanks.

show abstract

Section: Introductionmentioning

confidence: 98%

Investigation of Water Hammer Protection in Water Supply Pipeline Systems Using an Intelligent Self-Controlled Surge Tank

Wan

Zhang

2018

Energies

View full text Add to dashboard Cite

show abstract

“…The results revealed adiabatic behavior of the closed surge tank. Zhou et al [32] studied the power-off transient characteristics of a PSH station in pump mode using a three-dimensional (3D) unsteady numerical method based on a single-phase and VOF coupled model.…”

Section: Introductionmentioning

confidence: 99%

Transient Simulation of Underground Pumped Storage Hydropower Plants Operating in Pumping Mode

Menéndez¹,

Oro

Galdo

et al. 2020

Energies

View full text Add to dashboard Cite

The increasing penetration of variable renewable energies (VRE) in the European electricity mix requires flexible energy storage systems (ESS), such as pumped storage hydropower (PSH). Disused mining voids from deep closed mines may be used as subsurface reservoirs of underground pumped-storage hydropower (UPSH) plants. Unlike conventional PSH plants, the air pressure in UPSH plants is variable and it differs from the atmospheric conditions. In this paper, the hydraulic transient process of an UPSH plant operating in pumping mode was investigated and a preliminary thermodynamic analysis of the closed surge tank was carried out. Analytical and CFD three-dimensional numerical simulations based on the volume of fluid (VOF) model with two-phase flow have been performed for analyzing the transient process. In the transient simulation, air and water are considered as ideal gas and compressible liquid, respectively. Different guide vanes closing schemes have been simulated. The obtained results show that the dimensioning of underground reservoir, surge tank, and air ducts is essential for ensuring the hydraulic performance and optimizing the operation of UPSH plants. The static pressure in the air duct, surge tank and lower reservoir reaches −1.6, 112.8 and −4 kPa, respectively, while a heat flux of −80 W was obtained through the surge tank walls.

show abstract

“…However, the MOC technique generally focuses on the overall water conveyance system, including long penstocks or tail water channels, and therefore it cannot obtain detailed information regarding the internal flow field of the turbine. Currently, three dimensional (3D) numerical simulation methods that are based on computational fluid dynamics (CFD) have been increasingly applied for evaluating the transient characteristics of hydraulic turbines [26,27]. For example, Pavesi et al [28] conducted numerical simulations of a pump-turbine during the transient load following process in pump mode, and a full 3D flow structure was observed in the wicket gate channel, owing to boundary layer separation and stalling at lower rotational speeds.…”

Section: Introductionmentioning

confidence: 99%

Numerical Study on Flow Characteristics in a Francis Turbine during Load Rejection

et al. 2019

Self Cite

View full text Add to dashboard Cite

Labyrinth seals are not usually included in the numerical models of hydraulic machinery to simplify the geometric modeling, and thereby reduce the calculation burden. However, this simplification affects the numerical results, especially in the load rejection process, because disc friction losses, volume losses, and pressure fluctuations in the seal ring (SR) clearance passage are neglected. This paper addresses the issue by considering all of the geometrical details of labyrinth seals when conducting multiscale flow simulations of a high head Francis turbine under a transient load rejection condition using the commercial software code. A comparison of the numerical results that were obtained with the experimental testing data indicates that the calculated values of both torque and mass discharge rate are 8.65% and 5% slightly less than the corresponding values that were obtained from experimental model testing, respectively. The obtained pressure fluctuations of the Francis turbine in the vaneless zone and the draft tube appear to more closely match with the experimental test data when including SR clearance. Moreover, the flow rates through SR clearance passages were very small, but the pressure fluctuations among them were significantly enhanced under the minimal load condition. The numerical model with SR clearance can more accurately reflect the fact that the water thrust on the runner only fluctuates from 800 N to 575 N during the load rejection process, even though the water thrust on the blades varies from −220 N to 1200 N. Therefore, multiscale flow study is of great significance in understanding the effect of clearance flow on the load rejection process in the Francis turbine.

show abstract

Investigation of Pumped Storage Hydropower Power-Off Transient Process Using 3D Numerical Simulation Based on SP-VOF Hybrid Model

Cited by 36 publications

References 34 publications

Investigation of Water Hammer Protection in Water Supply Pipeline Systems Using an Intelligent Self-Controlled Surge Tank

Investigation of Water Hammer Protection in Water Supply Pipeline Systems Using an Intelligent Self-Controlled Surge Tank

Transient Simulation of Underground Pumped Storage Hydropower Plants Operating in Pumping Mode

Numerical Study on Flow Characteristics in a Francis Turbine during Load Rejection

Contact Info

Product

Resources

About