0

Full Content is available to subscribers

Subscribe/Learn More  >

Identification of Francis Turbine Helical Vortex Rope Excitation by CFD and Resonance Simulation With the Hydraulic System

[+] Author Affiliations
Sébastien Alligné, François Avellan

Laboratory for Hydraulic Machines, EPFL, Lausanne, Switzerland

Christophe Nicolet

Power Vision Engineering sàrl, Ecublens, Switzerland

Paper No. AJK2011-06089, pp. 481-493; 13 pages
doi:10.1115/AJK2011-06089
From:
  • ASME-JSME-KSME 2011 Joint Fluids Engineering Conference
  • ASME-JSME-KSME 2011 Joint Fluids Engineering Conference: Volume 1, Symposia – Parts A, B, C, and D
  • Hamamatsu, Japan, July 24–29, 2011
  • Conference Sponsors: Fluids Engineering Division
  • ISBN: 978-0-7918-4440-3
  • Copyright © 2011 by ASME

abstract

Due to the growing development of new renewable energies, which production is difficult to foreseen, power grid is subjected to disturbances. Hydropower plants are one of the solution to restore the grid stability by allowing hydraulic machines, especially Francis turbines, to change quickly of operating points in a very large range of heads and power in order to cover the variation of the electrical demand. In part load conditions, the cavitating vortex rope is an excitation source for the whole hydraulic circuit. The frequency of the excitation may matches with one of the eigenfrequency of the system leading to resonance phenomena. The aim of this paper is to simulate this hydroacoustic resonance by identifying the excitation source with CFD numerical simulations of the cavitating vortex rope and simulating the response of the hydraulic system with a one dimensional compressible model. A one dimensional draft tube model including three key parameters is used: the excitation momentum source corresponding to the force induced by the vortex rope acting on the wall, the excitation mass source induced by the cavitation volume fluctuations and the thermodynamic damping modeling energy dissipation during the phase change between cavitation and liquid. These parameters are computed for the FLINDT reduced scale model with the help of unsteady CFD simulations considering both one phase and two phase simulations. Finally these parameters are injected in the one dimensional hydroacoustic model to simulate the resonance phenomenon. In out of resonance conditions, maximum of pressure fluctuations are found in the draft tube cone with an amplitude of 1% of the turbine head. However, when resonance occurs, maximum amplitude of pressure fluctuations reaches up to 6.8%.

Copyright © 2011 by ASME

Figures

Tables

Interactive Graphics

Video

Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In