Experimental Investigation of Discharge Coefficient of Smooth-Crested Pattern Notches Entitled of Various Profiles

Abstract

Notches are common and useful devices in flow measurements in open channels. Precise estimation of discharge and coefficient of discharge in open channels is critical in hydraulic structures. Overestimation of discharge may cause failure to the structure. If the discharge is underestimated, it may not fulfill the design requirements. Present work focus on systematic experimentation for patterned triangular notches with different geometrical parameters. The main objective is to optimize the profile of patterned triangular notch to ensure the optimum discharge and coefficient of discharge. Governing equation for coefficient of discharge for patterned triangular notch is established based on the principle of notch flow, with consideration of the water depth, height and width of the notch. The impacts of various geometrical parameters of patterned triangular notch on the discharge coefficient are investigated. The new shape of notch is entitled to increase the coefficient of discharge, and to improve their hydraulic characteristics. Results indicated that discharge coefficient of the patterned shape triangular notch is greater than conventional notch.