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Repeatability and oblique flow response characteristics of current meters

Janice M. Fulford·Kirk G. Thibodeaux·William R. Kaehrle
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Abstract

Laboratory investigation into the precision and accuracy of various mechanical-current meters are presented. Horizontal-axis and vertical-axis meters that are used for the measurement of point velocities in streams and rivers were tested. Meters were tested for repeatability and response to oblique flows. Both horizontal- and vertical-axis meters were found to under- and over-register oblique flows with errors generally increasing as the velocity and angle of flow increased. For the oblique flow tests, magnitude of errors were smallest for horizontal-axis meters. Repeatability of all meters tested was good, with the horizontal- and vertical-axis meters performing similarly.

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Janice M. Fulford, Kirk G. Thibodeaux, William R. Kaehrle. 1993. Repeatability and oblique flow response characteristics of current meters. https://pubs.usgs.gov/publication/70017980

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