Инд. авторы:	Chirkov D.V., Shcherbakov P.K., Cherny S.G., Skorospelov V.A., Turuk P.A.
Заглавие:	Numerical investigation of the air injection effect on the cavitating flow in Francis hydro turbine
Библ. ссылка:	Chirkov D.V., Shcherbakov P.K., Cherny S.G., Skorospelov V.A., Turuk P.A. Numerical investigation of the air injection effect on the cavitating flow in Francis hydro turbine // Thermophysics and Aeromechanics. - 2017. - Vol.24. - Iss. 5. - P.691-703. - ISSN 0869-8643. - EISSN 1531-8699.
Внешние системы:	DOI: 10.1134/S0869864317050055; РИНЦ: 35523954; SCOPUS: 2-s2.0-85038882716; WoS: 000418306000005;
Реферат:	eng: At full and over load operating points, some Francis turbines experience strong self-excited pressure and power oscillations. These oscillations are occuring due to the hydrodynamic instability of the cavitating fluid flow. In many cases, the amplitude of such pulsations may be reduced substantially during the turbine operation by the air injection/ admission below the runner. Such an effect is investigated numerically in the present work. To this end, the hybrid one-three-dimensional model of the flow of the mixture “liquid−vapor” in the duct of a hydroelectric power station, which was proposed previously by the present authors, is augmented by the second gaseous component — the noncondensable air. The boundary conditions and the numerical method for solving the equations of the model are described. To check the accuracy of computing the interface “liquid−gas”, the numerical method was applied at first for solving the dam break problem. The algorithm was then used for modeling the flow in a hydraulic turbine with air injection below the runner. It is shown that with increasing flow rate of the injected air, the amplitude of pressure pulsations decreases. The mechanism of the flow structure alteration in the draft tube cone has been elucidated, which leads to flow stabilization at air injection. © 2017, Pleiades Publishing, Ltd.
Ключевые слова:	Three-dimensional model; Self excited oscillation; Numerical investigations; Hydroturbines; Hydroelectric power station; Hydrodynamic instabilities; Francis hydro-turbine; Air injection; Numerical models; Numerical methods; Hydroelectric power; Hydraulic turbines; Hydraulic motors; Flow of fluids; Cavitation; self-excited oscillations; numerical modeling; hydro turbines; cavitation; air injection; Hydroelectric power plants; Phase interfaces;
Издано:	2017
Физ. характеристика:	с.691-703
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