Author(s): Javad Farhoudi; N. Shokri
Linked Author(s):
Keywords: Broad crested weir; Critical depth; Downstream face; Slope variation; Discharge efficiency; Submergence ratio
Abstract: Flow measurement is an essential requirement in water conveyance systems and irrigation networks. Various equipments and devices have been designed and developed to meet these needs. However, the main object in selecting an appropriate measuring device is its degree of accuracy, submergence limit, construction costs and geometrical simplicities. Broad crested rectangular weirs are ones which meet these requirements to acceptable extent and are widely used in water supply systems. The hydraulics of broad crested rectangular weirs have therefore, has absorbed a broad attraction since late nineteenth where, a huge technical papers and notes were reported by various researchers. The aim of this investigation is to study the flow characteristics over the broad crested rectangular weirs with sloped downstream face. In this paper the effect of downstream slope on discharge efficiency of weir and its sensitivity to downstream submergence ratio have been reported. The results showed a lesser increase of flow efficiency with variation of slope and considerable high submergence limit as the downstream slopes were decreased from vertical to 10 degrees. The results are promising to utilize the advantage of a mild sloped downstream face where a submerged flow condition are prevailed downstream of measuring structure.
Year: 2007