Numerical simulation of free flow over Gabion crump weirs

Journal of Water Science & Engineering

مقاله 5، دوره 6، شماره 14، شهریور 2016، صفحه 77-93   

نوع مقاله: Original Article

نویسندگان

Mohammad Tavakol-Sadrabadi^* ؛ Manouchehr Fathi Moghadam؛ Reza Mohammad Pur

graduated M.Sc. student in civil engineering-water and hydraulics structures

چکیده

Environmentally friendly nature and the direct impact of gabion weirs on the quality parameters of rivers as well as simple design and construction of such structures, has putted them under consideration in the recent years. In this research, Hydraulic parameters of gabion crump weirs including water surface profile, discharge coefficient and through flow discharge are investigated numerically in free flow condition using flow-3d software. A total number of 18 models comprising 6 different geometries studied in 3 different porosities of 43%,44% an 46%. Results indicate that increasing the average diameter of particles (d₅₀) leads to the increase of through flow discharge in addition to discharge coefficient and friction loss. Also increasing the side slopes of weirs, decreases the discharge coefficient and through flow discharge. In addition, it is shown that the downstream slope has a slightly larger effect on discharge coefficient where upstream slope’s effect on through flow discharge is higher. Finally, using multivariate non-linear regression analysis, experimental equations were developed in order to estimate the discharge coefficient and the through flow discharge.

کلیدواژه‌ها

discharge coefficient؛ gabion crump weirs؛ Numerical simulation؛ through flow discharge

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