Quantifying propagation characteristics of unconfined turbidity currents interacting with an obstacle within the slumping regime. Issue 4 (4th July 2019)

• Record Type: Journal Article
• Authors: Wilson, Richard I; Friedrich, Heide; Stevens, Craig
• Is Part Of: Journal of hydraulic research. Volume 57:Issue 4(2019)
• Page Start: 498
• Page End: 516
• Publication Date: 2019-07-04
• Subjects: Instability -- obstacle -- sediment-laden flow -- unconfined -- visualization; Hydraulics -- Research -- Periodicals; Hydraulic engineering -- Periodicals; Hydraulic engineering; Electronic journals; Periodicals; 621.2
• DOI: 10.1080/00221686.2018.1494054
• Languages: English
• ISSNs: 0022-1686

Abstract

ABSTRACT: Experimental studies of confined turbidity currents interacting with obstacles have become popular over the last three decades; however, little work has sought to quantify the characteristics of unconfined turbidity currents interacting with obstacles. In the present study, unconfined turbidity currents colliding with a rectangular basal obstruction are investigated. With a focus on the initial theoretical slumping regime, flow characteristics are quantified and characterized. The currents varied with initial density and substrate roughness. Unobstructed currents propagated at a constant velocity, confirming previous theory that the current is within the slumping regime; however, a typical reverse ambient bore was not present. Froude and Reynolds numbers were shown to decrease over the obstacle by 43–54% and 17%, respectively. Deflected lateral propagation along the obstacle face was found to entrap ambient fluid and encourage mixing, providing a starting point for understanding the implications of lateral propagation along submerged pipelines and reservoir barriers.