Oscillation of Cavitating Vortices in Draft Tubes of a Simplified Model Turbine and a Model Pump–Turbine

The self-oscillation of the cavitating vortices is one of the dangerous phenomena of hydraulic turbine operation near full-load conditions. This work is an attempt to generalize data and expand insight on the phenomenon of self-excited oscillations by comparing the experimental results obtained on a...

Full description

Bibliographic Details
Main Authors: Sergey Skripkin, Zhigang Zuo, Mikhail Tsoy, Pavel Kuibin, Shuhong Liu
Format: Article
Language:English
Published: MDPI AG 2022-04-01
Series:Energies
Subjects:
Online Access:https://www.mdpi.com/1996-1073/15/8/2965
_version_ 1797434754426994688
author Sergey Skripkin
Zhigang Zuo
Mikhail Tsoy
Pavel Kuibin
Shuhong Liu
author_facet Sergey Skripkin
Zhigang Zuo
Mikhail Tsoy
Pavel Kuibin
Shuhong Liu
author_sort Sergey Skripkin
collection DOAJ
description The self-oscillation of the cavitating vortices is one of the dangerous phenomena of hydraulic turbine operation near full-load conditions. This work is an attempt to generalize data and expand insight on the phenomenon of self-excited oscillations by comparing the experimental results obtained on a simplified turbine and scaled-down pump–turbine models. In both cases, a series of high-speed imaging was carried out, which made it possible to study these phenomena with high temporal resolution. The high-speed imaging data was subjected to additional processing such as binarization, cropping, and scaling. For a simplified turbine model, the volume of the vapor cavity was calculated based on the assumption of the axial symmetry of the cavity, after which fast Fourier transform (FFT) analysis was carried out. A proper orthogonal decomposition (POD) analysis was also performed to examine individual modes in the original digital imaging data. For the pump–turbine, visualization data on the cavitation cavity oscillations were supplemented by pressure measurements in the draft tube cone to determine the frequency characteristics. Based on obtained experimental data, an improved one-dimensional model describing the oscillations of the cavitation cavity arising behind the hydraulic turbine runner is proposed.
first_indexed 2024-03-09T10:37:34Z
format Article
id doaj.art-3eabffe38c32455eb7999007a86457f6
institution Directory Open Access Journal
issn 1996-1073
language English
last_indexed 2024-03-09T10:37:34Z
publishDate 2022-04-01
publisher MDPI AG
record_format Article
series Energies
spelling doaj.art-3eabffe38c32455eb7999007a86457f62023-12-01T20:51:05ZengMDPI AGEnergies1996-10732022-04-01158296510.3390/en15082965Oscillation of Cavitating Vortices in Draft Tubes of a Simplified Model Turbine and a Model Pump–TurbineSergey Skripkin0Zhigang Zuo1Mikhail Tsoy2Pavel Kuibin3Shuhong Liu4Laboratory of Advanced Energy Efficient Technologies, Physics Department, Novosibirsk State University, Novosibirsk 630090, RussiaState Key Laboratory of Eco-Hydraulics in Northwest Arid Region, Xi’an University of Technology, Xi’an 710048, ChinaLaboratory of Advanced Energy Efficient Technologies, Physics Department, Novosibirsk State University, Novosibirsk 630090, RussiaLaboratory of Advanced Energy Efficient Technologies, Physics Department, Novosibirsk State University, Novosibirsk 630090, RussiaState Key Laboratory of Hydro Science and Engineering, Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, ChinaThe self-oscillation of the cavitating vortices is one of the dangerous phenomena of hydraulic turbine operation near full-load conditions. This work is an attempt to generalize data and expand insight on the phenomenon of self-excited oscillations by comparing the experimental results obtained on a simplified turbine and scaled-down pump–turbine models. In both cases, a series of high-speed imaging was carried out, which made it possible to study these phenomena with high temporal resolution. The high-speed imaging data was subjected to additional processing such as binarization, cropping, and scaling. For a simplified turbine model, the volume of the vapor cavity was calculated based on the assumption of the axial symmetry of the cavity, after which fast Fourier transform (FFT) analysis was carried out. A proper orthogonal decomposition (POD) analysis was also performed to examine individual modes in the original digital imaging data. For the pump–turbine, visualization data on the cavitation cavity oscillations were supplemented by pressure measurements in the draft tube cone to determine the frequency characteristics. Based on obtained experimental data, an improved one-dimensional model describing the oscillations of the cavitation cavity arising behind the hydraulic turbine runner is proposed.https://www.mdpi.com/1996-1073/15/8/2965cavitating vorticesturbinepump–turbinehigh-speed visualizationproper orthogonal decomposition (POD)
spellingShingle Sergey Skripkin
Zhigang Zuo
Mikhail Tsoy
Pavel Kuibin
Shuhong Liu
Oscillation of Cavitating Vortices in Draft Tubes of a Simplified Model Turbine and a Model Pump–Turbine
Energies
cavitating vortices
turbine
pump–turbine
high-speed visualization
proper orthogonal decomposition (POD)
title Oscillation of Cavitating Vortices in Draft Tubes of a Simplified Model Turbine and a Model Pump–Turbine
title_full Oscillation of Cavitating Vortices in Draft Tubes of a Simplified Model Turbine and a Model Pump–Turbine
title_fullStr Oscillation of Cavitating Vortices in Draft Tubes of a Simplified Model Turbine and a Model Pump–Turbine
title_full_unstemmed Oscillation of Cavitating Vortices in Draft Tubes of a Simplified Model Turbine and a Model Pump–Turbine
title_short Oscillation of Cavitating Vortices in Draft Tubes of a Simplified Model Turbine and a Model Pump–Turbine
title_sort oscillation of cavitating vortices in draft tubes of a simplified model turbine and a model pump turbine
topic cavitating vortices
turbine
pump–turbine
high-speed visualization
proper orthogonal decomposition (POD)
url https://www.mdpi.com/1996-1073/15/8/2965
work_keys_str_mv AT sergeyskripkin oscillationofcavitatingvorticesindrafttubesofasimplifiedmodelturbineandamodelpumpturbine
AT zhigangzuo oscillationofcavitatingvorticesindrafttubesofasimplifiedmodelturbineandamodelpumpturbine
AT mikhailtsoy oscillationofcavitatingvorticesindrafttubesofasimplifiedmodelturbineandamodelpumpturbine
AT pavelkuibin oscillationofcavitatingvorticesindrafttubesofasimplifiedmodelturbineandamodelpumpturbine
AT shuhongliu oscillationofcavitatingvorticesindrafttubesofasimplifiedmodelturbineandamodelpumpturbine