000254927 001__ 254927
000254927 005__ 20181203025001.0
000254927 0247_ $$2doi$$a10.1016/j.ijmultiphaseflow.2018.03.022
000254927 02470 $$2DOI$$a10.1016/j.ijmultiphaseflow.2018.03.022
000254927 037__ $$aARTICLE
000254927 245__ $$aRotating air-water ring in the vaneless gap of a pump-turbine operating in condenser mode
000254927 260__ $$c2018
000254927 269__ $$a2018
000254927 336__ $$aJournal Articles
000254927 520__ $$aThe rotating air-water ring, featuring a bubbly flow, in the vaneless gap of a reduced scale physical model of a pump-turbine operating in dewatered condition is investigated. High speed visualizations are performed together with pressure fluctuation measurements to estimate the bubbles size, the velocity and pressure fields of the two-phase flow as a function of the cooling water discharge and of the gauge pressure in the draft tube cone of the pump-turbine. An image processing method is developed to compute the bubbles size and to estimate both tangential and radial velocity components of the bubbles. The results show that the size of the bubbles in the rotating air-water ring increases by increasing the gauge pressure while the cooling discharge through the labyrinth seals has no influence. The pressure and the velocity fields in both radial and tangential components are estimated as a function of the gauge pressure. Pressure fluctuations and the corresponding frequency are explored and correlated to the interaction of the rotating air-water ring with the rotating parts and the stationary parts of the pump-turbine. The modal decomposition of the harmonic components of the pressure fluctuation is analytically derived to evidence the rotor-stator interaction in the vaneless gap causing pressure fluctuation.
000254927 6531_ $$aBubbly flow
000254927 6531_ $$aImage processing
000254927 6531_ $$aVelocity profiles
000254927 6531_ $$aPressure fluctuations
000254927 6531_ $$aRotor-stator interaction
000254927 6531_ $$aDewatered hydraulic turbine
000254927 700__ $$aVagnoni, E.
000254927 700__ $$aAndolfatto, L.
000254927 700__ $$aGuillaume, R.
000254927 700__ $$aLeroy, P.
000254927 700__ $$aAvellan, F.
000254927 773__ $$tInternational Journal of Multiphase Flow
000254927 8560_ $$floic.andolfatto@epfl.ch
000254927 909C0 $$mfrancois.avellan@epfl.ch$$pLMH$$0252135$$xU10309
000254927 909CO $$pSTI$$particle$$ooai:infoscience.epfl.ch:254927
000254927 960__ $$aloic.andolfatto@epfl.ch
000254927 961__ $$amanon.velasco@epfl.ch
000254927 973__ $$rREVIEWED$$sPUBLISHED$$aEPFL
000254927 980__ $$aARTICLE
000254927 981__ $$aoverwrite