Effect of Types of Weir on Discharge

The measurement of discharge is one of the main concerns in hydraulic engineering. The study of types of weir on discharge is important as the knowledge of the accurate measurement of discharges helps in understanding of the flow mechanism as well as designing the hydraulic structures for future. Structures such as rectangular weir, vee notch weir and crump weir are placed in a channel to measure the flow rate. By using Bernoulli’s equation, weir equation are derived and used to determine the flow rate. The main objective is to determine the optimum discharge for different types of weirs. This discharge is important in designing the hydraulic structure. Overestimated discharge may cause failure to the structure and if the discharge is underestimated, it may not fulfill the design requirements. The studies are experimented from maximum flow to minimum flow by measuring head over the weir for different working sections; flat and slope of 1:2400 and different height of partially opened sluice gate of 4cm and 6cm for crump drowned condition. The result shows that the coefficient of discharge, Cd decreases when the head of water above the crest increases; except for crump weir in which Cd is independent of the head. Meanwhile, the velocities when slope is 1:2400 are higher as compared to flat.