Documents disponibles écrits par cet auteur

Estimation of discharge in compound channels based on energy concept / Zhonghua Yang in Journal of hydraulic research, Vol. 50 N° 1 (Janvier/Février 2012) 

Public ISBD [article]  in Journal of hydraulic research > Vol. 50 N° 1 (Janvier/Février 2012) . - pp. 105-113 Titre : Estimation of discharge in compound channels based on energy concept Type de document : texte imprimé Auteurs : Zhonghua Yang, Auteur ; Wei Gao, Auteur ; Wenxin Huai, Auteur Année de publication : 2012 Article en page(s) : pp. 105-113 Note générale : hydraulique Langues : Anglais (eng) Mots-clés : Compound  channel  Discharge  Energy  conversation  Energy  loss  Overbank  flow Résumé : A new model is developed to estimate the discharge capacity in straight, symmetric, compound open channels based on the energy concept. The energy loss and the transition mechanism in these channels are analysed based on mechanical analysis, in which the momentum transfer mechanism is taken into account as a product of the apparent shear stress. Four representative formulae of apparent shear stress are selected to validate the present model; the results indicate that the performance of the present model depends on our ability to accurately predict the apparent shear stress. The comparisons with experimental data indicate that the most appropriate apparent shear stress formula is that of Moreta and Martín-Vide; however, for the compound channels without roughness differences between the main channel and floodplains, Christodoulou's formula is still recommended for its simplicity. Comparisons with other models indicate that the present models are simple in manipulation and have a reasonable accuracy for engineering purposes. DEWEY : 627 ISSN : 0022-1686 En ligne : http://www.tandfonline.com/doi/abs/10.1080/00221686.2011.638212 [article] Estimation of discharge in compound channels based on energy concept [texte imprimé] / Zhonghua Yang, Auteur ; Wei Gao, Auteur ; Wenxin Huai, Auteur . - 2012 . - pp. 105-113. hydraulique Langues : Anglais (eng) in Journal of hydraulic research > Vol. 50 N° 1 (Janvier/Février 2012) . - pp. 105-113 Mots-clés : Compound  channel  Discharge  Energy  conversation  Energy  loss  Overbank  flow Résumé : A new model is developed to estimate the discharge capacity in straight, symmetric, compound open channels based on the energy concept. The energy loss and the transition mechanism in these channels are analysed based on mechanical analysis, in which the momentum transfer mechanism is taken into account as a product of the apparent shear stress. Four representative formulae of apparent shear stress are selected to validate the present model; the results indicate that the performance of the present model depends on our ability to accurately predict the apparent shear stress. The comparisons with experimental data indicate that the most appropriate apparent shear stress formula is that of Moreta and Martín-Vide; however, for the compound channels without roughness differences between the main channel and floodplains, Christodoulou's formula is still recommended for its simplicity. Comparisons with other models indicate that the present models are simple in manipulation and have a reasonable accuracy for engineering purposes. DEWEY : 627 ISSN : 0022-1686 En ligne : http://www.tandfonline.com/doi/abs/10.1080/00221686.2011.638212

Uniform laminar wetland flow through submerged and floating plants / Mingdeng Zhao in Journal of hydraulic research, Vol. 50 N° 1 (Janvier/Février 2012) 

Public ISBD [article]  in Journal of hydraulic research > Vol. 50 N° 1 (Janvier/Février 2012) . - pp. 52-59 Titre : Uniform laminar wetland flow through submerged and floating plants Type de document : texte imprimé Auteurs : Mingdeng Zhao, Auteur ; Wenxin Huai, Auteur ; Jie Han, Auteur Année de publication : 2012 Article en page(s) : pp. 52-59 Note générale : Hydraulique Langues : Anglais (eng) Mots-clés : Habitat  restoration  Laminar  flow  Porous  media  Stormwater  treatment  Vegetation  flow  Wetland Résumé : Wetland flow is currently actively studied because of its applications in stormwater management, wastewater treatment and habitat restoration. This research applies the well-established poroelastic media flow theory to uniform laminar wetland flow through submerged and floating vegetation, where the linear interaction between the pore water and the vegetation skeleton is considered in the equations of motion. The effects of vegetation porosity on the velocity, the shear stress and the energy distributions in different layers are first derived analytically and interpreted graphically and physically. As special cases, the homogeneous water flow, as also floating, submerged and emergent vegetation flows are then discussed. This research provides qualitative understanding of wetland flow on velocity, shear stress and energy distributions, indicating that a plant applies a significant resistance to the flow system and dissipates most of the flow energy. The results serve a benchmark framework for the future study on turbulent vegetation flow. DEWEY : 627 ISSN : 0022-1686 En ligne : http://www.tandfonline.com/doi/abs/10.1080/00221686.2011.641327 [article] Uniform laminar wetland flow through submerged and floating plants [texte imprimé] / Mingdeng Zhao, Auteur ; Wenxin Huai, Auteur ; Jie Han, Auteur . - 2012 . - pp. 52-59. Hydraulique Langues : Anglais (eng) in Journal of hydraulic research > Vol. 50 N° 1 (Janvier/Février 2012) . - pp. 52-59 Mots-clés : Habitat  restoration  Laminar  flow  Porous  media  Stormwater  treatment  Vegetation  flow  Wetland Résumé : Wetland flow is currently actively studied because of its applications in stormwater management, wastewater treatment and habitat restoration. This research applies the well-established poroelastic media flow theory to uniform laminar wetland flow through submerged and floating vegetation, where the linear interaction between the pore water and the vegetation skeleton is considered in the equations of motion. The effects of vegetation porosity on the velocity, the shear stress and the energy distributions in different layers are first derived analytically and interpreted graphically and physically. As special cases, the homogeneous water flow, as also floating, submerged and emergent vegetation flows are then discussed. This research provides qualitative understanding of wetland flow on velocity, shear stress and energy distributions, indicating that a plant applies a significant resistance to the flow system and dissipates most of the flow energy. The results serve a benchmark framework for the future study on turbulent vegetation flow. DEWEY : 627 ISSN : 0022-1686 En ligne : http://www.tandfonline.com/doi/abs/10.1080/00221686.2011.641327