Jets Opposing Turbidity Currents and Open Channel Flows

• Published in: Journal of hydraulic engineering (New York, N.Y.) Vol. 139; no. 1; pp. 55 - 59
• Main Authors: Bühler, J, Oehy, Ch, Schleiss, A. J
• Format: Journal Article
• Language: English
• Published: Reston, VA American Society of Civil Engineers 01.01.2013
• Subjects: Applied sciences; Buildings. Public works; Exact sciences and technology; Fluid dynamics; Hydraulic constructions; Jets; Mathematical analysis; Obstacles; Open channel flow; Reservoirs; Sedimentation; Technical Note; Technical Notes; Turbidity; Gravity current; Sediment; Open channel flow; Baffle block; Reservoir; Experimental study; Hydraulic jump; Sedimentation; Jets (fluid); Flow control; Jet; Reservoirs; Currents; Turbidity current
• ISSN: 0733-9429; 1943-7900
• DOI: 10.1061/(ASCE)HY.1943-7900.0000639

AbstractHydraulic jumps at the tail end of spillways are usually induced by baffle blocks or other obstacles. Such jumps can also be induced by jets that oppose the main flow. Another application is to back up turbidity currents in reservoirs by means of opposing jets. This measure can be adopted when transfer tunnels feed water into the reservoir at a higher elevation near the dam. Stopping the turbidity current increases the local sedimentation rate. To reconcile the shallow water equations for turbidity currents with those for open channel flows, mass-based scales for the depth and velocity of both types of flows are outlined. The continuity and momentum equation for flows opposed by jets are then stated in terms of these scales and expressed by a single curve for both gravity currents and free surface flows. The corresponding results for free surface flows agree well with those of experiments carried out for this study. An application to turbidity currents is provided as well.