Performance characteristics of a water current meter in water and in air

Abstract

The effect of density on the performance of a water current meter of the cup-wheel type, known as the small Price meter, was investigated by calibrating the meter first in water by towing it in a rating tank, and second in air by placing the meter in a wind tunnel. The change from water to air produced a change in density by a fact or of approximately 800. It was found that the revolutions of the cup wheel during 1 foot of travel of the fluid was a fun ction of the product of velocity by the square root of the density and that R eynolds number and turbulence have no measurable effect. It was concluded that changes of density occurring in field use can cause no appreciable error.