Research output: Contribution to journal › Article › peer-review
Three-dimensional simulation of full load instability in Francis turbines. / Chirkov, Denis V.; Cherny, Sergey G.; Shcherbakov, Pavel K. et al.
In: Journal of Hydraulic Research, Vol. 57, No. 5, 03.09.2019, p. 623-634.Research output: Contribution to journal › Article › peer-review
}
TY - JOUR
T1 - Three-dimensional simulation of full load instability in Francis turbines
AU - Chirkov, Denis V.
AU - Cherny, Sergey G.
AU - Shcherbakov, Pavel K.
AU - Skorospelov, Vladimir A.
AU - Zakharov, Alexander V.
PY - 2019/9/3
Y1 - 2019/9/3
N2 - Full load instability is one of the most dangerous unsteady flow phenomena, and practically restricts the zone of stable operation of the whole hydraulic power plant. This paper presents a mathematical model and a numerical method for simulation of full load instability and the resulting pressure pulsations in Francis turbines. The model consists of one-dimensional hydro-acoustic equations for a long penstock domain, and three-dimensional Reynolds averaged Navier–Stokes equations of “liquid-vapour” flow for the turbine domain. Series of computations of a high head hydraulic power plant are carried out. Investigated are the sensitivities to time step and mesh size refinements as well as the effect of turbulence model. Thoma number and operating point dependencies of the computed amplitude and frequency of pressure pulsations are compared to measurements and to the predictions of the fully one-dimensional model of the power plant. The amplitude of the computed pressure and power oscillations agree well with the available experimental data, showing the potential of the presented approach to investigate and predict high load pulsations in hydraulic power plants.
AB - Full load instability is one of the most dangerous unsteady flow phenomena, and practically restricts the zone of stable operation of the whole hydraulic power plant. This paper presents a mathematical model and a numerical method for simulation of full load instability and the resulting pressure pulsations in Francis turbines. The model consists of one-dimensional hydro-acoustic equations for a long penstock domain, and three-dimensional Reynolds averaged Navier–Stokes equations of “liquid-vapour” flow for the turbine domain. Series of computations of a high head hydraulic power plant are carried out. Investigated are the sensitivities to time step and mesh size refinements as well as the effect of turbulence model. Thoma number and operating point dependencies of the computed amplitude and frequency of pressure pulsations are compared to measurements and to the predictions of the fully one-dimensional model of the power plant. The amplitude of the computed pressure and power oscillations agree well with the available experimental data, showing the potential of the presented approach to investigate and predict high load pulsations in hydraulic power plants.
KW - Cavitation
KW - flow instabilities
KW - Francis turbine
KW - numerical simulation
KW - three-dimensional models
KW - water pipelines
KW - NUMERICAL-SIMULATION
KW - FLOW
UR - http://www.scopus.com/inward/record.url?scp=85052337205&partnerID=8YFLogxK
U2 - 10.1080/00221686.2018.1494047
DO - 10.1080/00221686.2018.1494047
M3 - Article
AN - SCOPUS:85052337205
VL - 57
SP - 623
EP - 634
JO - Journal of Hydraulic Research/De Recherches Hydrauliques
JF - Journal of Hydraulic Research/De Recherches Hydrauliques
SN - 0022-1686
IS - 5
ER -
ID: 16336649