Open AccessInvestigation of fluid transients in a penstock attached to a Francis turbine rig using seismic interferometry
Author(s) -
Magnus Farstad Perkunder,
Torbjørn Kristian Nielsen,
Céline Faudot
Publication year - 2019
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1266/1/012010
Subject(s) - penstock , interferometry , hydropower , reflection (computer programming) , turbine , geology , acoustics , francis turbine , engineering , computer science , structural engineering , physics , optics , mechanical engineering , electrical engineering , programming language
Pressure fluctuations in hydropower plants contribute to fatigue loads. Pressure pulsations generated by a reaction turbine will create fluid transients in the attached system which can increase the load on structural parts if resonance occurs. Several factors govern transients in a pipe system where the main parameters are the length between reflection points and the propagation velocity. This paper investigates how to find the propagation velocity of pressure waves measured in the penstock at the Hydropower Laboratory at NTNU by applying techniques from seismic interferometry. A simple 1-D model has been developed using the method of characteristics to compare the experimental results to a known system. Seismic interferometry is primarily used in academic and research settings, the basic principle is to obtain the Green’s function between measured signals. The results from the experimental data and simulations are promising, but further research is needed to optimize both data acquisition and post processing.