Free Impinging Jets Scouring, Using Numerical Model

Document Type : پژوهشی


1 Semnan University.

2 Semnan University

3 Civil Engineering Faculty, All-e Taha University.


Investigation on local scour phenomenon downstream of impinging jets is very complicated. Different parameters such as geometry of stream, characteristics of flow and sediments have great influences on the scour phenomenon. The present study is preceded to numerical modeling of scouring by impinging jet via SSIIM 2 model founded on a physical model tests. The numerical model is calibrated for roughness coefficient, turbulence model and the bed load sediment transport function by using the coefficient of determination and the mean absolute error. Effects of Froude number, densimeteric Froude number and drop height on scouring by impinging jet were investigated. The results indicate that the maximum scour depth increases by increasing Froude number; densimeteric Froude number and drop height.


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