Selecting the most appropriate sediment transport equations by numerical model HEC-RAS.4.1 (Case Study: Markazi Province Qara-chai River)

Document Type : Research

Authors

1 Education and Research Organization of the Ministry of Jihad and Agriculture

2 Lorestan University

Abstract

Estimation of total sediment load or transmission rate is one of the critical approaches in the field of water resources projects. The aim of this study is to estimate the amount of sediments and calculation of transport power of Qara-Chai River in the Markazi Province through different Methods. For this research a rich  of 31 km was selected. After the basic information such as cross sections, geometrical features of path, roughness coefficients of, bed and laterals, suspended and bed sediment genus and grain size were extracted. Also, sediment discharge was estimated by HEC-RAS model. The results showed that equations of Englund-Hansen and Tuffalti don’t have significant difference with measured data at 5 percent level error. Meyer-Peter and Muller, Wilcocks, Acker -White and Laursen methods significantly differed which those observed (P<0.05). So sediment transport capacity increased from up to down because of increasing longitudinal slope so that in the final one third the highest changes exist.

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