000186538 001__ 186538
000186538 005__ 20180317092216.0
000186538 022__ $$a1001-6279
000186538 02470 $$2ISI$$a000316807700002
000186538 037__ $$aARTICLE
000186538 245__ $$aReduction of bend scour with an air-bubble screen - morphology and flow patterns
000186538 260__ $$aBeijing$$bIrtces$$c2013
000186538 269__ $$a2013
000186538 300__ $$a9
000186538 336__ $$aJournal Articles
000186538 500__ $$a[896]
000186538 520__ $$aThe interplay between streamwise flow, curvature-induced secondary flow, sediment transport and bed morphology leads to the formation of a typical bar-pool bed morphology in open-channel bends. The associated scour at the outer bank and deposition at the inner bank may endanger the outer bank's stability or reduce the navigable width of the channel. Previous preliminary laboratory experiments in a sharply curved flume with a fixed horizontal bed have shown that a bubble screen located near the outer bank can generate an additional secondary flow located between the outer bank and the curvature-induced secondary flow and with a sense of rotation opposite to the latter. This bubble-induced secondary flow redistributes velocities and bed shear stresses. The reported study investigates the implications of a bubble screen on the flow and the morphology in configurations with mobile bed. Velocity measurements show that the bubble-induced secondary flow shifts the curvature-induced secondary flow in inwards direction and reduces its strength. The bubble screen considerably reduces morphological gradients. Maximum bend scour is reduced by about 50% and occurs further away from the outer bank where it does not endanger the bank stability anymore. The location of maximum scour coincides with the junction of the curvature-induced and bubble-induced secondary flows. At this same location, the maximum streamwise velocities and maximum vertical velocities impinging on the bed also occur, which indicates their importance with respect to the formation of bend scour. The bubble screen also substantially reduced deposition at the inner bank. These preliminary experiments show the potential of a bubble screen to influence and modify the bed morphology.
000186538 6531_ $$aBubble screen
000186538 6531_ $$aErosion
000186538 6531_ $$aScour
000186538 6531_ $$aMorphodynamics
000186538 6531_ $$aOpen-channel bend
000186538 700__ $$0242671$$aDugue, Violaine$$g188310$$uEcole Polytech Fed Lausanne, Lab Hydraul Construct LCH, CH-1015 Lausanne, Switzerland
000186538 700__ $$0241199$$aBlanckaert, Koen$$g112543$$uEcole Polytech Fed Lausanne, Lab Hydraul Construct LCH, CH-1015 Lausanne, Switzerland
000186538 700__ $$aChen, Qiuwen
000186538 700__ $$0241228$$aSchleiss, Anton J.$$g112841$$uEcole Polytech Fed Lausanne, Lab Hydraul Construct LCH, CH-1015 Lausanne, Switzerland
000186538 773__ $$j28$$k1$$q15-23$$tInternational Journal Of Sediment Research
000186538 8564_ $$s2667317$$uhttps://infoscience.epfl.ch/record/186538/files/2013-896_Dugu%C3%A9_Blanckaert_Chen_Schleiss_.pdf$$yn/a$$zn/a
000186538 909CO $$ooai:infoscience.tind.io:186538$$pENAC$$particle
000186538 909C0 $$0252079$$pLCH$$xU10263
000186538 917Z8 $$x206365
000186538 917Z8 $$x206365
000186538 937__ $$aEPFL-ARTICLE-186538
000186538 973__ $$aEPFL$$rREVIEWED$$sPUBLISHED
000186538 980__ $$aARTICLE