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Evaluating Various Factors in Calculation of Scour Depth around Bridge Piers Using HEC-RAS Software, CSU2001 and Froehlich Equations Original Article, C59 Mousavi S.F and Daneshfaraz R. Journal. Civil Eng. Urban. 3(6):398-402. 2013 ABSTRACT:Today, scour is one of the important issues in river and coastal engineering science. Most of the existing structures exposed to the flowing water are destroyed by this phenomenon. Determining relationship between parameters influencing scour depth and maximum depth of scour, and also finding dominant function of them is one of the important issues in hydraulic engineering. Many equations and software have been presented by researchers to calculate local scour, such as Hec-Ras software. Ignorable errors of this software in vitro test make it one of the nominated options in evaluating local scour depth. Hec-Ras software uses CSU and Froehlich (1991) equations to calculate local scour. In this study, software output and manual calculation output of CSU and Froehlich equations were compared. Results of empirical equations and Hec-Ras in the scattering length of Haraz River were compared with each other to create equal hydrological and hydraulic conditions. Reviewing the Froude number, its measurement, and the effective coefficients of common empirical equations and software has significant effect on changes of these parameters in the results. The study also indicate that equations used in Hec-Ras will have acceptable results if their coefficients are examined with sufficient engineering , accurate perspective and controlling use or non-use of coefficients in ranges closer to the defined boundary. Keywords:Local Scour, Empirical Equations of Local Scour, Froude Number, Bridge Pier, Hec-Ras منبع: [Hidden Content] دانلود: [Hidden Content].,59-398-402.pdf J. Civil Eng. Urban.,59-398-402.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