Velocity Measurements in Transient Flow Downstream of a Submerged Vertical Drop

Retsinis, Eugene; Papanicolaou, Panos

dc.contributor.author	Retsinis, Eugene
dc.contributor.author	Papanicolaou, Panos	en
dc.date.accessioned	2022-08-29T13:58:14Z
dc.date.available	2022-08-29T13:58:14Z
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/55563
dc.identifier.uri	http://dx.doi.org/10.26240/heal.ntua.23261
dc.rights	Αναφορά Δημιουργού-Μη Εμπορική Χρήση-Όχι Παράγωγα Έργα 3.0 Ελλάδα	*
dc.rights.uri	http://creativecommons.org/licenses/by-nc-nd/3.0/gr/	*
dc.subject	Velocity Measurements	en
dc.title	Velocity Measurements in Transient Flow Downstream of a Submerged Vertical Drop	en
heal.type	conferenceItem
heal.classification	Open Channel Hydraulics	en
heal.contributorName	Retsinis, Eugene
heal.contributorName	Papanicolaou, Panos	en
heal.language	en
heal.access	free
heal.recordProvider	ntua	el
heal.publicationDate	2022-09-09
heal.bibliographicCitation	Eugene Retsinis and Panos Papanicolaou, (2022). Velocity Measurements in Transient Flow Downstream of a Submerged Vertical Drop, 7th IAHR Europe Congress, Innovative Water Management in a Changing Climate, September 7th-9th, Athens, Greece	en
heal.abstract	Hydraulic jumps occur when supercritical flow becomes subcritical under momentum conservation conditions and is used as energy dissipation mechanism in the design of stilling basins. In some cases a vertical negative step is constructed at the entrance of a stilling basin in order to stabilize the hydraulic jump under all operating conditions. In laboratory experiments the flow is controlled by a sluice gate upstream, and a sharp crested overflow downstream of the step. Five different rapidly varying types of flow have been observed around a step under supercritical flow conditions upstream (Moore and Morgan, 1957, Ohtsu and Yasuda, 1991, Mossa et al. 2003) The minimum B-jump is the hydraulic jump at the toe of the step, the B-jump is a submerged jump downstream of the step, the wave-train is a transient, surface jet-type flow without formation of a hydraulic jump, the wave-jump is the flow of an ascending jet forming a standing wave downstream of the step, before it dives and results in a submerged hydraulic jump, and the A-jump is the flow where the hydraulic jump is formed upstream of the step. These flow profiles appear with this sequence by increasing the tailwater depth downstream continuously. The transition from supercritical to subcritical flow over a fully submerged negative step has been studied by experiments regarding the measurement of flow depths upstream and downstream of the jump as well as the pressure at the face of the step, but not the internal turbulent flow properties in terms of velocity measurements. Aim of the present work is the measurement of the two-dimensional velocity field in the region of a wave-train using Particle Image Velocimetry (PIV) for three upstream Froude numbers 1.99, 2.55 and 2.99.	en
heal.fullTextAvailability	false
heal.conferenceName	7th IAHR Europe Congress, Innovative Water Management in a Changing Climate	en
heal.conferenceItemType	short paper