Experimental Hydro-Mechanical Characterization of Full Load Pressure Surge in Francis Turbines

A. Müller, Arthur Tristan Favrel, C. Landry, K. Yamamoto, F. Avellan

Research output: Contribution to journalConference article

3 Citations (Scopus)

Abstract

Full load pressure surge limits the operating range of hydro-electric generating units by causing significant power output swings and by compromising the safety of the plant. It appears during the off-design operation of hydraulic machines, which is increasingly required to regulate the broad integration of volatile renewable energy sources into the existing power network. The underlying causes and governing physical mechanisms of this instability were investigated in the frame of a large European research project and this paper documents the main findings from two experimental campaigns on a reduced scale model of a Francis turbine. The multi-phase flow in the draft tube is characterized by Particle Image Velocimetry, Laser Doppler Velocimetry and high-speed visualizations, along with synchronized measurements of the relevant hydro-mechanical quantities. The final result is a comprehensive overview of how the unsteady draft tube flow and the mechanical torque on the runner shaft behave during one mean period of the pressure oscillation, thus defining the unstable fluid-structure interaction responsible for the power swings. A discussion of the root cause is initiated, based on the state of the art. Finally, the latest results will enable a validation of recent RANS flow simulations used for determining the key parameters of hydro-acoustic stability models.

Original languageEnglish
Article number012018
JournalJournal of Physics: Conference Series
Volume813
Issue number1
DOIs
Publication statusPublished - 2017 Apr 4
Externally publishedYes
EventHYdropower Plants PERformance and FlexiBle Operation Towards Lean Integration of New Renewable Energies Symposium, HYPERBOLE 2017 - Porto, Portugal
Duration: 2017 Feb 22017 Feb 3

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Fingerprint Dive into the research topics of 'Experimental Hydro-Mechanical Characterization of Full Load Pressure Surge in Francis Turbines'. Together they form a unique fingerprint.

  • Cite this