caa a22 4500 445874716 CHVBK 20180317145524.0 cr unu---uuuuu 170323e20111001xx s 000 0 eng 10.1007/s10652-010-9192-x doi (NATIONALLICENCE)springer-10.1007/s10652-010-9192-x Near-critical free-surface flows: real fluid flow analysis [Elektronische Daten] [Oscar Castro-Orgaz, Hubert Chanson] An open channel flow with a flow depth close to the critical depth is characterised by a curvilinear streamline flow field that results in steady free surface undulations. Near critical flows of practical relevance encompass the undular hydraulic jump when the flow changes from supercritical (F>1) to subcritical (F<1), and the undular weir flow over broad-crested weirs where the flow changes from subcritical (F<1) to supercritical (F>1). So far these flows were mainly studied based on ideal fluid flow computations, for which the flow is assumed irrotational and, thus, shear forces are absent. While the approach is accurate for critical flow conditions (F=1) in weir and flumes, near-critical flows involve long distances reaches, and the effect of friction on the flow properties cannot be neglected. In the present study the characteristics of near-critical free-surface flows are reanalysed based on a model accounting for both the streamline curvature and friction effects. Based on the improved model, some better agreement with experimental results is found, thereby highlighting the main frictional features of the flow profiles. Springer Science+Business Media B.V., 2010 Open channels nationallicence Near-critical flows nationallicence Frictional effects nationallicence Hydraulic jump nationallicence Transitional flow nationallicence Turbulence nationallicence Undular flow nationallicence Castro-Orgaz Oscar Instituto de Agricultura Sostenible, Consejo Superior de Investigaciones Cientificas, Finca Alameda del Obispo, 14080, Cordoba, Spain aut Chanson Hubert Hydraulic Engineering, School of Civil Engineering, The University of Queensland, 4072, Brisbane, QLD, Australia aut Environmental Fluid Mechanics Springer Netherlands 11/5(2011-10-01), 499-516 1567-7419 11:5<499 2011 11 10652 https://doi.org/10.1007/s10652-010-9192-x text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10652-010-9192-x text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Castro-Orgaz Oscar Instituto de Agricultura Sostenible, Consejo Superior de Investigaciones Cientificas, Finca Alameda del Obispo, 14080, Cordoba, Spain aut NATIONALLICENCE 700 1- Chanson Hubert Hydraulic Engineering, School of Civil Engineering, The University of Queensland, 4072, Brisbane, QLD, Australia aut NATIONALLICENCE 773 0- Environmental Fluid Mechanics Springer Netherlands 11/5(2011-10-01), 499-516 1567-7419 11:5<499 2011 11 10652 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer