Effect of bed roughness on the propagation of negative surges in rivers and estuaries
نویسندگان
چکیده
In an open channel, a sudden drop in water elevation is associated with a negative surge. Practical applications include the ebb tide motion in estuaries with macro-tidal conditions, the rundown of the swash, and the retreat of tsunami waters after reaching the maximum runup. Herein a physical study is presented with a focus on the effects of bed roughness. Detailed measurements were performed in a large facility with three roughness types. The results are presented and practical applications are discussed. Mots clefs : Ondes négatives, Rugosité de fond, Ecoulements à surface libre, Ecoulement instationnaire
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