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3-D Underflow of a Sluice Gate at a Channel Inlet; Experimental Results and CFD Simulations Original Article, D75 Calomino F. and Lauria A. J. Civil Eng. Urban. 4(5): 501-508. 2014 ABSTRACT: The underflow of a sluice gate is well known when the gate is set into a channel of the same width (2-D underflow), while no studies are found in the literature when the gate is flush with the wall of the tank or reservoir upstream to the channel (3-D underflow). Experimental and numerical investigations were carried out to study the flow in this case, in a small range of relative openings, considering three wall slopes, and obtaining an equation for the discharge coefficient. Afterwards, numerical simulations were performed by means of a CFD (Computational Fluid Dynamics) model, following the RANS approach and based on a finite-volume computational code. Comparison of experimental and numerical results showed that the simulations predict accurately the flow behaviour; thereafter discharge coefficients in a more extended range of relative openings were computed for use in the practice. Keywords: Channel Inlet, Sluice Gate, 3-D Underflow, Discharge Coefficients, CFD Simulations. منبع: [Hidden Content] دانلود: [Hidden Content].,%204%20(5)%20501-508,%202014.pdf J. Civil Eng. Urban., 4 (5) 501-508, 2014.pdf

The Effect of a Sluice Gate Edge on Water Surface Profile Original Article, B42 Mohammed A.Y, and Khaleel M.S. Journal. Civil Eng. Urban. 2(6): 239-243. 2012. ABSTRACT:In this paper the effect of the lower gate edge on the water surface profile (W.S.P) have been studied in a rectangular flume with four gate openings (2, 3, 4 and 4.5) cm, five upstream of water heads (18.9,21,24,26 and 28.9) cm and five gate cases (vertical and inclined vertically by angle (45)o with and opposite to flow direction )with horizontal and sharp lower edge ( inclined by angle (45)o ) Were adopted in the experiments. The results show that the convergence length for inclined gate with flow direction and horizontal edge increases by (28.7)"%" with respect to vertical, while decreases by (21.4)"%" when gate inclined opposite to flow direction and horizontal edge. The convergence angle decreases by (38.7)"%" when gate inclined with flow direction and horizontal edge, while increase by (22.4)"%" when gate inclined opposite flow direction and horizontal edge. The horizontal lip for the inclined gate with flow direction reduced the (W.S.P) convergence angle and then reduced the scour downstream sluice gate. Keywords:sluice gate, water surface profile, tail water, finite elements منبع: [Hidden Content] دانلود: [Hidden Content],%20B%2042%20239-243.pdf JCEU, B 42 239-243.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

Numerical Investigation of Sluice Gates' Shape Factor on Contraction Coefficient Original Article, B13 Sadeghfam S and Akhtari AA. Journal. Civil Eng. Urban. 2(2): 72-74. 2012. ABSTRACT:The behavior of flow under sluice gate and determining the water profile is one of the important issues in hydraulic engineering. In this study the contraction coefficient is studied and the effect of slice gate's shape is observed numerically by CFD model. The turbulence model k-e (RNG) and unsteady flow mode are used in analysis of two dimensional gates. Three types of slice gate's shapes are analyzed and contraction coefficient of these cases is presented and compared with experimental and theoretical results of other researchers. It is worth mentioning that for these cases the equations in terms of the ratio of gate opening to depth of approaching flow behind gate, are collected. So the gate's shape has significant role on contraction coefficient and between 3 types of gate's shapes that are investigated in this research, contraction coefficient of the sluice gate with shape of two side slope (case 3) has larger amount of this coefficient. Keywords: Sluice Gate, CFD model, Contraction Coefficient, Turbulence Model k-e (RNG) منبع: [Hidden Content] دانلود: [Hidden Content].,B13-72-74.pdf J. Civil Eng. Urban.,B13-72-74.pdf