Experimental Investigations on Upper Part Load Vortex Rope Pressure Fluctuations in Francis Turbine Draft Tube
نویسندگان
چکیده
منابع مشابه
Numerical simulation of a cavitating draft tube vortex rope in a Francis turbine at part load conditions for different σ-levels
In the present study, numerical investigations of a Francis turbine at model scale are performed. A part load operating point is selected for the analysis with a focus on the cavitating draft tube vortex rope. For three σ-levels, different aspects are investigated. First, the extension of the vapor volume is analyzed and compared to high-speed visualization recordings from the measurements. Fur...
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Acoustic resonances in Francis turbines often define undesirable limitations to their operating ranges at high load. The knowledge of the mechanisms governing the onset and the sustenance of these instabilities in the swirling flow leaving the runner is essential for the development of a reliable hydroacoustic model for the prediction of system stability. The present work seeks to study experim...
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The prediction of pressure and output power fluctuations amplitudes on Francis turbine prototype is a challenge for hydro-equipment industry since it is subjected to guarantees to ensure smooth and reliable operation of the hydro units. The European FP7 research project Hyperbole aims to setup a methodology to transpose the pressure fluctuations induced by the cavitation vortex rope from the re...
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With economical energy market strategies based on instantaneous pricings of electricity as function of the demand or the predictions, operators harness more hydroelectric facilities to off-design operating points to cover the variations of the electricity production. Under these operating conditions, Francis turbines develop a cavitating swirling flow at the runner outlet which induces pressure...
متن کاملMethodology for Risk Assessment of Part Load Resonance in Francis Turbine Power Plant
At low flow rate operation, Francis turbines feature a cavitating vortex rope in the draft tube resulting from the swirling flow of the runner outlet. The unsteady pressure field related to the precession of the vortex rope induces plane wave propagating in the entire hydraulic system. The frequency of the vortex rope precession being comprised between 0.2 and 0.4 times the turbine rotational s...
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ژورنال
عنوان ژورنال: International Journal of Fluid Machinery and Systems
سال: 2011
ISSN: 1882-9554
DOI: 10.5293/ijfms.2011.4.1.179