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Experimental Study of Bell-Mouth Intakes on Discharge Coefficient Original Article, C54 Naderi V, Farsadizadeh D, Hosseinzadeh Dalir A, Arvanaghi H. Journal. Civil Eng. Urban. 3(6):368-371. 2013 ABSTRACT:The strong vortices at the mouth of an intake reduce the discharge efficiency. One of the solutions for controlling the vortex is the use of bell-mouth intakes. Since only general guidance for use of bell-mouth intakes is available a study for the more shapes of mouth of intake is needed. Hence, a comprehensive set of experiments have been carried out using 4 different mouth-shapes of a vertical intake. The results showed that with reducing the radius of curvature of bell-mouth intake, the coefficient of discharge rate increased, and maximum discharge coefficient with four different mouth shape of intake with the radius of curvature of 2d was created. Keywords:Discharge coefficient, bell-mouth intake, vortex, radius of curvature of mouth of intake منبع: [Hidden Content] دانلود: [Hidden Content].,54-368-371.pdf J. Civil Eng. Urban.,54-368-371.pdf

Sharp-Crested Weir Discharge Coefficient Original Article, C14 Arvanaghi, H., Nasehi Oskuei, N Journal. Civil Eng. Urban. 3(3):87-91 . 2013 ABSTRACT:Weirs are useful and common devices in flow measurements. The essential parameter of each weir is to determine the flow coefficient. In this study, laboratory measurements of the water surface profile, approach flow velocity and flow rate carried out over three different rectangular sharp-crested weirs mounted in a flume. The flow was then numerically simulated by the CFD commercial software Fluent v. 6.2 in several stages. Results show that Fluent can model the flow over this type of weirs preciously. Then the effect of three dimensionless parameters of weir height (H/W), Froude number and Reynolds number on weir discharge coefficient is investigated using experimental and numerical data. For a specific value of these parameters, discharge coefficient is tending to the fixed value of 0.7. Keywords:Sharp-Crested Weir, CFD, Discharge Coefficient, Weir Height, Froude Number, Reynolds Number منبع: [Hidden Content] دانلود: [Hidden Content] JCEU-C3-15.pdf

Vertical Sluice Gate Discharge Coefficient Original Article, B20 Nasehi Oskuyi N, Salmasi F. Journal. Civil Eng. Urban. 2(3): 108-114. 2012. ABSTRACT:Sluice gates are widely used for flow control and discharge measurement in irrigation and drainage channels. Their discharge coefficient depends on geometric and hydraulic parameters. Errors are inevitable when their values are abstracted from empirical curves for a range of reasons including the resolution of the graphs, judgments in reading the values, the need for their digital values at the computational stages. This study develops two equations, linear and nonlinear, to determine discharge coefficient by using dimensional analysis and linear and nonlinear regression analysis, for both free and submerged flow conditions. A total of 5200 data point was generated, which involved different effective hydraulic parameters. The study also included the results of the past studies carried out by different investigators concerning sluice gate discharge coefficient determination for comparison purposes. The performance of the nonlinear equation improves in comparison with the linear equation. All numerical computations were carried out by Wolfram Mathematica v.6 software. Keywords: Discharge coefficient, free flow, multiple regressing, sluice gate, submerged flow منبع: [Hidden Content] دانلود: [Hidden Content],%20108-114,%202012.pdf JCEU-B20, 108-114, 2012.pdf