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Scour formation due to simultaneous circular impinging jet and wall jet / Mojtaba Mehraein in Journal of hydraulic research, Vol. 50 N° 4 (Juillet/Août 2012) 

Public ISBD [article]  in Journal of hydraulic research > Vol. 50 N° 4 (Juillet/Août 2012) . - pp. 395-399 Titre : Scour formation due to simultaneous circular impinging jet and wall jet Type de document : texte imprimé Auteurs : Mojtaba Mehraein, Auteur ; Masoud Ghodsian, Auteur ; Anton J. Schleiss, Auteur Année de publication : 2012 Article en page(s) : pp. 395-399 Note générale : Hydraulique Langues : Anglais (eng) Mots-clés : Densimetric  Froude  number  Impinging  jet  Laboratory  experiment  Scour  Wall  jet Résumé : Experiments involving both a circular wall jet and an impinging jet were conducted, as occurring at irrigation control structures or at dams with combined crest and low-level spillways. The effects of the non-dimensional parameters on the scour hole dimensions have been investigated. It was found that the effect of the expansion ratio of the channel width to the jet diameter is negligible for values larger than 22.5 and 35, depending on the experimental conditions. The scour depth decreases with increasing tailwater depth and the horizontal distance between the impinging jet and the origin of the wall jet. The scour length and the distance between the end of the ridge and the wall jet origin increase with decreasing densimetric Froude number of the impinging jet. The opposite trend occurs for decreasing densimetric Froude number of the wall jet. An empirical relationship for estimating the scour depth due to the simultaneous jet action is given. ISSN : 0022-1686 En ligne : http://www.tandfonline.com/doi/full/10.1080/00221686.2012.694174 [article] Scour formation due to simultaneous circular impinging jet and wall jet [texte imprimé] / Mojtaba Mehraein, Auteur ; Masoud Ghodsian, Auteur ; Anton J. Schleiss, Auteur . - 2012 . - pp. 395-399. Hydraulique Langues : Anglais (eng) in Journal of hydraulic research > Vol. 50 N° 4 (Juillet/Août 2012) . - pp. 395-399 Mots-clés : Densimetric  Froude  number  Impinging  jet  Laboratory  experiment  Scour  Wall  jet Résumé : Experiments involving both a circular wall jet and an impinging jet were conducted, as occurring at irrigation control structures or at dams with combined crest and low-level spillways. The effects of the non-dimensional parameters on the scour hole dimensions have been investigated. It was found that the effect of the expansion ratio of the channel width to the jet diameter is negligible for values larger than 22.5 and 35, depending on the experimental conditions. The scour depth decreases with increasing tailwater depth and the horizontal distance between the impinging jet and the origin of the wall jet. The scour length and the distance between the end of the ridge and the wall jet origin increase with decreasing densimetric Froude number of the impinging jet. The opposite trend occurs for decreasing densimetric Froude number of the wall jet. An empirical relationship for estimating the scour depth due to the simultaneous jet action is given. ISSN : 0022-1686 En ligne : http://www.tandfonline.com/doi/full/10.1080/00221686.2012.694174