scholarly journals Numerical investigation on transient flow of a high head pump-turbine in pump mode during rapid closure of guide vanes

2017 ◽  
Author(s):  
Giorgio Pavesi ◽  
Wenjie Wang
Keyword(s):  
Numerical Investigation ◽  
Transient Flow ◽  
Pump Mode ◽  
Pump Turbine ◽  
Guide Vanes ◽  
High Head

Numerical investigation on transient flow of a high head low specific speed pump-turbine in pump mode

2015 ◽  
Vol 7 (6) ◽  
pp. 063111 ◽  
Author(s):  
Deyou Li ◽  
Ruzhi Gong ◽  
Hongjie Wang ◽  
Xianzhu Wei ◽  
Zhansheng Liu ◽  
...  
Keyword(s):  
Numerical Investigation ◽  
Transient Flow ◽  
Pump Mode ◽  
Pump Turbine ◽  
Low Specific Speed ◽  
High Head ◽  
Specific Speed

scholarly journals Numerical Investigation in the Vaned Distributor under Different Guide Vanes Openings of a Pump Turbine in Pump Mode

2016 ◽  
Vol 9 (1) ◽  
pp. 253-266 ◽  
Author(s):  
Deyou Li ◽  
Ruzhi Gong ◽  
Hongjie Wang ◽  
Jian Zhang ◽  
Xianzhu Wei ◽  
...  
Keyword(s):  
Numerical Investigation ◽  
Pump Mode ◽  
Pump Turbine ◽  
Guide Vanes

scholarly journals Distribution of Pressure Fluctuations in a Prototype Pump Turbine at Pump Mode

2014 ◽  
Vol 6 ◽  
pp. 923937 ◽  
Author(s):  
Yuekun Sun ◽  
Zhigang Zuo ◽  
Shuhong Liu ◽  
Jintao Liu ◽  
Yulin Wu
Keyword(s):  
Mass Flow ◽  
Pressure Fluctuations ◽  
Dominant Frequency ◽  
Pump Mode ◽  
Pump Turbine ◽  
Guide Vanes ◽  
Path Direction ◽  
Mass Flow Rates ◽  
Operating Points ◽  
Spiral Casing

Pressure fluctuations are very important characteristics in pump turbine's operation. Many researches have focused on the characteristics (amplitude and frequencies) of pressure fluctuations at specific locations, but little researches mentioned the distribution of pressure fluctuations in a pump turbine. In this paper, 3D numerical simulations using SSTk − ω turbulence model were carried out to predict the pressure fluctuations distribution in a prototype pump turbine at pump mode. Three operating points with different mass flow rates and different guide vanes’ openings were simulated. The numerical results show how pressure fluctuations at blade passing frequency (BPF) and its harmonics vary along the whole flow path direction, as well as along the circumferential direction. BPF is the first dominant frequency in vaneless space. Pressure fluctuation component at this frequency rapidly decays towards upstream (to draft tube) and downstream (to spiral casing). In contrast, pressure fluctuations component at 3BPF spreads to upstream and downstream with almost constant amplitude. Amplitude and frequencies of pressure fluctuations also vary along different circumferential locations in vaneless space. When the mass flow and guide vanes’ opening are different, the distribution of pressure fluctuations along the two directions is different basically.

scholarly journals Numerical simulation prediction of pressure distribution of guide vanes in a high-head pump turbine

2021 ◽  
Vol 774 (1) ◽  
pp. 012038
Author(s):  
Lei He ◽  
Zhongxin Gao ◽  
Ying Chen ◽  
Jianguang Zhang ◽  
Bingquan Ma ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Pressure Distribution ◽  
Pump Turbine ◽  
Guide Vanes ◽  
High Head

Transient characteristics during the closure of guide vanes in a pump-turbine in pump mode

2018 ◽  
Vol 118 ◽  
pp. 973-983 ◽  
Author(s):  
Deyou Li ◽  
Hongjie Wang ◽  
Zhenggui Li ◽  
Torbjørn Kristian Nielsen ◽  
Rahul Goyal ◽  
...  
Keyword(s):  
Pump Mode ◽  
Pump Turbine ◽  
Transient Characteristics ◽  
Guide Vanes

scholarly journals The Influence of Flow Rates on Pressure Fluctuation in the Pump Mode of Pump-Turbine with Splitter Blades

2020 ◽  
Vol 10 (19) ◽  
pp. 6752
Author(s):  
Ping Huang ◽  
Yajing Xiao ◽  
Jinfeng Zhang ◽  
Haikun Cai ◽  
Haiqin Song
Keyword(s):  
Pressure Fluctuation ◽  
Draft Tube ◽  
Guide Vane ◽  
Pump Mode ◽  
Pump Turbine ◽  
Flow Rates ◽  
Guide Vanes ◽  
Rotor Stator Interaction ◽  
Computational Fluid Dynamics Cfd ◽  
The Stability

This paper takes a pump-turbine as the research subject and, based on the Computational Fluid Dynamics (CFD) numerical method and combined with test data, investigates the pressure fluctuation characteristics in the pump mode and analyzes the pressure fluctuation characteristics at 0.75 Qd, 1.0 Qd and 1.25 Qd when the guide vane opening is 17.5°. The results showed that the protruding frequencies of pressure fluctuation in the bladeless region were mainly 5 fn, 10 fn and 20 fn, and the main frequencies in the runner area and near the outlet wall of the draft tube were 16 fn and 5 fn, respectively. At different heights for the guide vanes, the pressure fluctuation in the bladeless region had significant differences, and the pressure fluctuation near the bottom ring was the most intense. The amplitude of the rotor–stator interaction frequency continuously attenuates from the bladeless region to the outlet of the stay vanes, and the amplitude attenuation of each frequency is mainly concentrated in the area of the guide vanes. In this paper, the influence of different flow rates on the pressure fluctuation in the pump mode is analyzed, which provides a theoretical reference for the stability and further study of pump-turbines.

Measurement of Unsteady Flow in Pump-Turbine for Hydropower Using PIV Method

2009 ◽  
Author(s):  
Nobuhiko Fukuda ◽  
Satoshi Someya ◽  
Koji Okamoto
Keyword(s):  
Rotational Speed ◽  
Velocity Measurement ◽  
Numerical Procedure ◽  
Hydraulic Turbine ◽  
Operating Conditions ◽  
High Time ◽  
Pump Turbine ◽  
Guide Vanes ◽  
Runner Blade ◽  
Wide Range

It is thought that the pressure fluctuation can occur due to the interaction between flow through guide vanes and flow into runner blades, resulting in a vibration of turbine and a blade cracking, in a hydraulic turbine operated in a wide range for flexible power demand. High accurate velocity measurement with high time/spatial resolution can help to clarify the mechanism of the interaction and to provide good experimental data for the validation of numerical procedure. So the aim of present study is to estimate the unstable velocity field quantitatively in the area between guide vanes and runner blades, using high time-resolved particle image velocimetry (PIV). Two types of velocity measurements were carried out, i.e., phase-locked measurement and high time sequential velocity measurement, in a pump-turbine model with 20 guide vanes and 6 runner blades. The characteristic of the flow field varied corresponding to the operating conditions such as flow rate and rotational speed. Opening angles of guide vanes were kept uniform. A clockwise vortex was generated at inside of the runner blade under smaller rotational speed. A counterclockwise vortex was separated at the backside of the runner blade under higher rotational speed. At any operating conditions, the velocity between guide vanes and runner blades oscillated periodically at the blade passing frequency.

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