Discharge Formula and Tables for Sharp-Crested Suppressed Weirs

The new discharge formula presented in this paper applies to sharp-crested weirs that occupy the full width of the channel; that is, weirs with the end contractions suppressed. This formula is entirely empirical and was developed by a mathematical study of the results of a series of weir experiments made at Cornell 1Jniversity by E. W. Schoder, M. Am. Soc. C. E., and the late Kenneth B. Turner, Assistant Professor of Hydraulics. It differs from those in use at present in that a variable exponent, increasing with the head, replaces the customary fixed exponent (1.5), thus making it possible to obtain accurate discharges, even at low heads, by a comparatively simple form of coefficient. Furthermore, correction for the velocity of approach, which has been developed, depends entirely on the physical dimensions of the weir and can be applied directly.

Curves in this paper offer a comparison between the results of the Schoder and Turner experiments in comparison with the new formula and with the three standard formulas of Francis, Bazin, and Rehbock. These three standard formulas differ from one another, but each is supported by the experimental data, over certain ranges of head and height of weir; however, over the entire range of head and height of weir covered by the experiments, the new formula agrees with the data more closely than any of these standard formulas. A set of complete tables for use in applying the new formula has been placed on record in Engineering Societies Library, New York, N. Y.