DefinePK

Abstract

Flow measurement in open channel is important to support the system management. An experimental study in a laboratory flume is carried out to study flow over a sharp crested weir and under gate in combined structure as flow measurement device. Four different oblique angles to the longitudinal axis of the channel and four different heights of gate opening were used. The basic principles of statistical analysis are employed to correlate between the hydraulic and geometric dimensionless parameters with the discharge coefficient. Different relationship models with acceptable significance are suggested. It was found that the major parameters effecting significantly on discharge coefficient are (h/d, α, L/d, P/d), and value of Cd range from 0.623 to 0.403, with Standard Error 0.0047. Within the limitations of the present experimental work two different discharge equations were predicted. The first equation Which assumed that the coefficient of discharge is the same for weir and gate with R2 of o.972, and the second which assumed that there is different percent of discharge for each weir and gate with R2 of 0.997.