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Predicting oxygen transfer efficiency at low-head gated sill structures / Adam M. Witt in Journal of hydraulic research, Vol. 50 N° 5 (Septembre/Octobre 2012) 

Public ISBD [article]  in Journal of hydraulic research > Vol. 50 N° 5 (Septembre/Octobre 2012) . - pp. 521-531 Titre : Predicting oxygen transfer efficiency at low-head gated sill structures Type de document : texte imprimé Auteurs : Adam M. Witt, Auteur ; John S. Gulliver, Auteur Année de publication : 2012 Article en page(s) : pp. 521-531 Note générale : Hydraulique Langues : Anglais (eng) Mots-clés : Aerated  flows  Air–water  interface  interactions  Bubble  dynamics  Flow–structure  interactions  Gas  transfer  Hydraulic  jump  Water  quality Résumé : An improved model for predicting oxygen transfer efficiency at gated sills is presented. An analysis of field measurements from eight gated sill structures is used to develop a dimensionless relationship between inflow conditions, dam geometry and oxygen transfer efficiency. The oxygen transfer coefficient is estimated from scaled formulations of the liquid film coefficient, mean bubble diameter, air entrainment rate and turbulent energy dissipation rate. The model is validated with additional field measurements adjusted for temperature and effective saturation concentration. A design parameter for gated sill dams is introduced giving a relationship between gate opening and oxygen transfer efficiency. Improved prediction of oxygen transfer in the field is a tool that can be used to successfully operate gated structures to meet oxygen concentration requirements and to assist in the design of remediation technologies. ISSN : 0022-1686 En ligne : http://www.tandfonline.com/doi/abs/10.1080/00221686.2012.729163 [article] Predicting oxygen transfer efficiency at low-head gated sill structures [texte imprimé] / Adam M. Witt, Auteur ; John S. Gulliver, Auteur . - 2012 . - pp. 521-531. Hydraulique Langues : Anglais (eng) in Journal of hydraulic research > Vol. 50 N° 5 (Septembre/Octobre 2012) . - pp. 521-531 Mots-clés : Aerated  flows  Air–water  interface  interactions  Bubble  dynamics  Flow–structure  interactions  Gas  transfer  Hydraulic  jump  Water  quality Résumé : An improved model for predicting oxygen transfer efficiency at gated sills is presented. An analysis of field measurements from eight gated sill structures is used to develop a dimensionless relationship between inflow conditions, dam geometry and oxygen transfer efficiency. The oxygen transfer coefficient is estimated from scaled formulations of the liquid film coefficient, mean bubble diameter, air entrainment rate and turbulent energy dissipation rate. The model is validated with additional field measurements adjusted for temperature and effective saturation concentration. A design parameter for gated sill dams is introduced giving a relationship between gate opening and oxygen transfer efficiency. Improved prediction of oxygen transfer in the field is a tool that can be used to successfully operate gated structures to meet oxygen concentration requirements and to assist in the design of remediation technologies. ISSN : 0022-1686 En ligne : http://www.tandfonline.com/doi/abs/10.1080/00221686.2012.729163