Experimental Study on Hysteresis during Cavitating Vortex Onset in Pump-as-Turbine Applications

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26210%2F26%3A0199815" target="_blank" >RIV/00216305:26210/26:0199815 - isvavai.cz</a>

Výsledek na webu

<a href="https://iopscience.iop.org/article/10.1088/1755-1315/1561/1/012017" target="_blank" >https://iopscience.iop.org/article/10.1088/1755-1315/1561/1/012017</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1088/1755-1315/1561/1/012017" target="_blank" >10.1088/1755-1315/1561/1/012017</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Experimental Study on Hysteresis during Cavitating Vortex Onset in Pump-as-Turbine Applications

Popis výsledku v původním jazyce

Centrifugal pumps operating in turbine mode (pump-as-turbine) have become a relatively common solution for small-scale hydropower plants and for energy recovery applications. One of the aspects of pump-as-turbine (PaT) operation is that the pump impeller is generally designed for exclusive operation in pump mode. Therefore, significant residual swirl exits the impeller in turbine mode and creates a dominant swirling motion in the discharge pipe. The magnitude of this swirling flow depends on the operating mode of the PaT. Due to inconvenient blade angles, the swirling motion with coherent vortices might be the dominant component even under the best efficiency operating conditions. The present study focuses on the experimental analysis of the cavitating vortex developed downstream in the discharge pipe. The effect of hysteresis on vortex dynamics is assessed with regard to increase and decrease of cavitation number. The primary concern is with the frequency and amplitude measured by the pressure sensor downstream of PaT. These results are correlated with the image analysis of the cavitating vortex shape recorded by the high-speed camera. The results indicated that the main source of hysteresis is caused by self-induced instabilities of the cavitating vortex. The description and understanding of this phenomenon is important for further correlation of CFD simulations with measured data and for reliable operation of PaTs.

Název v anglickém jazyce

Experimental Study on Hysteresis during Cavitating Vortex Onset in Pump-as-Turbine Applications

Popis výsledku anglicky

Centrifugal pumps operating in turbine mode (pump-as-turbine) have become a relatively common solution for small-scale hydropower plants and for energy recovery applications. One of the aspects of pump-as-turbine (PaT) operation is that the pump impeller is generally designed for exclusive operation in pump mode. Therefore, significant residual swirl exits the impeller in turbine mode and creates a dominant swirling motion in the discharge pipe. The magnitude of this swirling flow depends on the operating mode of the PaT. Due to inconvenient blade angles, the swirling motion with coherent vortices might be the dominant component even under the best efficiency operating conditions. The present study focuses on the experimental analysis of the cavitating vortex developed downstream in the discharge pipe. The effect of hysteresis on vortex dynamics is assessed with regard to increase and decrease of cavitation number. The primary concern is with the frequency and amplitude measured by the pressure sensor downstream of PaT. These results are correlated with the image analysis of the cavitating vortex shape recorded by the high-speed camera. The results indicated that the main source of hysteresis is caused by self-induced instabilities of the cavitating vortex. The description and understanding of this phenomenon is important for further correlation of CFD simulations with measured data and for reliable operation of PaTs.

Druh

D - Stať ve sborníku

CEP obor

—

OECD FORD obor

20302 - Applied mechanics

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2025

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název statě ve sborníku

IOP Conference Series: Earth and Environmental Science

ISBN

—

ISSN

1755-1307

e-ISSN

1755-1315

Počet stran výsledku

6

Strana od-do

1-6

Název nakladatele

IOP Publishing

Místo vydání

online

Místo konání akce

Brno, Czech Republic

Datum konání akce

1. 10. 2025

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

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