Cavitation Erosion in Hydroturbines
Publication: Journal of Hydraulic Engineering
Volume 115, Issue 10
Abstract
This paper is based on a field survey of the operational and design characteristics of 729 hydroturbines installed since 1950 having either a capacity in excess of 20 MW or a discharge diameter greater than 3 m. This data base includes 67% of the total U.S. hydropower capacity (40,000 MW). A nondimensional erosion rate parameter is developed to make meaningful comparison of observed cavitation erosion rate with theory and laboratory experiments. Overall design parameters such as specific speed and unit speed for a given head are found to have little variation from manufacturer to manufacturer. However, cavitation erosion rate varies widely even when relative comparisons are made. These variations are attributable to variations in setting, manufacturing tolerances, and operational history of a given unit. Size effects appear more pronounced than predicted. Direct repair costs are only about 1.5 cents per megawatt hour, but hidden costs associated with reductions in useful life or degradation of efficiency or energy production losses could be very significant.
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Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 115 • Issue 10 • October 1989
Pages: 1297 - 1315
Copyright
Copyright © 1989 ASCE.
History
Published online: Oct 1, 1989
Published in print: Oct 1989
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