Date of this Version
The U.S. Geological Survey (USGS) has undertaken the task of conducting an evaluation of the USGS's standard water-flow current meter, the Price type-AA current meter. The first part of the USGS's task was to conduct a comprehensive literature review to determine the extent and types of testing that has been conducted to evaluate the performance of various types of current meters used for open-channel flow measurements. The meter types included in the review were the vertical-axis mechanical type, the horizontal-axis mechanical type, the electromagnetic type, and the point-velocity acoustic (ultrasonic) type current meters. The review revealed that current meters have been systematically tested since the 1890's. The testing covered in the literature consisted of evaluating the performance of current meters subjected to various methods of standard calibration techniques, to oscillatory flow (vertical, horizontal, and axial), to oblique flow (vertical and horizontal angles of flow), proximity to boundaries, turbulence effects, and temperature effects.