On the combined effect of bed elevation discordances in the main-river and the tributary in 90° straight-channel confluences
Апстракт
The role of the difference in bed elevations in the main-river (ΔzMR) and the tributary (ΔzT) at their entrance to a 90° straight-channel confluence is studied numerically using a 3D finite-volume model. Three characteristic hydrological scenarios with DR = QMR/Qtot = {0.250, 0.583, 0.750} (where QMR and Qtot are flow discharges in the main-river upstream and downstream of the confluence, respectively) are analysed in nine confluence layouts having ΔzMR/hd ε[0.10, 0.50] and ΔzT/hd ε[0.10, 0.50] (where hd stands for the flow depth in the deeper channel at the confluence). It is found that the presence of the bed-step in the main river: 1) does not affect the flow and bed shear stress distributions for DR = 0.250, 2) causes inclination of the recirculation zone and reduces its size for DR > 0.5, 3) favours conditions for the bed-load transport both in and far downstream of the confluence when DR ≠ 0.750 regardless of the ΔzT-value.
Извор:
River Flow - Proceedings of the International Conference on Fluvial Hydraulics, RIVER FLOW 2016, 2016, 1616-1625Издавач:
- CRC Press/Balkema
Scopus: 2-s2.0-85015333169
Колекције
Институција/група
GraFarTY - CONF AU - Đorđević, Dejana AU - Stojnić, Ivan PY - 2016 UR - https://grafar.grf.bg.ac.rs/handle/123456789/748 AB - The role of the difference in bed elevations in the main-river (ΔzMR) and the tributary (ΔzT) at their entrance to a 90° straight-channel confluence is studied numerically using a 3D finite-volume model. Three characteristic hydrological scenarios with DR = QMR/Qtot = {0.250, 0.583, 0.750} (where QMR and Qtot are flow discharges in the main-river upstream and downstream of the confluence, respectively) are analysed in nine confluence layouts having ΔzMR/hd ε[0.10, 0.50] and ΔzT/hd ε[0.10, 0.50] (where hd stands for the flow depth in the deeper channel at the confluence). It is found that the presence of the bed-step in the main river: 1) does not affect the flow and bed shear stress distributions for DR = 0.250, 2) causes inclination of the recirculation zone and reduces its size for DR > 0.5, 3) favours conditions for the bed-load transport both in and far downstream of the confluence when DR ≠ 0.750 regardless of the ΔzT-value. PB - CRC Press/Balkema C3 - River Flow - Proceedings of the International Conference on Fluvial Hydraulics, RIVER FLOW 2016 T1 - On the combined effect of bed elevation discordances in the main-river and the tributary in 90° straight-channel confluences EP - 1625 SP - 1616 UR - https://hdl.handle.net/21.15107/rcub_grafar_748 ER -
@conference{ author = "Đorđević, Dejana and Stojnić, Ivan", year = "2016", abstract = "The role of the difference in bed elevations in the main-river (ΔzMR) and the tributary (ΔzT) at their entrance to a 90° straight-channel confluence is studied numerically using a 3D finite-volume model. Three characteristic hydrological scenarios with DR = QMR/Qtot = {0.250, 0.583, 0.750} (where QMR and Qtot are flow discharges in the main-river upstream and downstream of the confluence, respectively) are analysed in nine confluence layouts having ΔzMR/hd ε[0.10, 0.50] and ΔzT/hd ε[0.10, 0.50] (where hd stands for the flow depth in the deeper channel at the confluence). It is found that the presence of the bed-step in the main river: 1) does not affect the flow and bed shear stress distributions for DR = 0.250, 2) causes inclination of the recirculation zone and reduces its size for DR > 0.5, 3) favours conditions for the bed-load transport both in and far downstream of the confluence when DR ≠ 0.750 regardless of the ΔzT-value.", publisher = "CRC Press/Balkema", journal = "River Flow - Proceedings of the International Conference on Fluvial Hydraulics, RIVER FLOW 2016", title = "On the combined effect of bed elevation discordances in the main-river and the tributary in 90° straight-channel confluences", pages = "1625-1616", url = "https://hdl.handle.net/21.15107/rcub_grafar_748" }
Đorđević, D.,& Stojnić, I.. (2016). On the combined effect of bed elevation discordances in the main-river and the tributary in 90° straight-channel confluences. in River Flow - Proceedings of the International Conference on Fluvial Hydraulics, RIVER FLOW 2016 CRC Press/Balkema., 1616-1625. https://hdl.handle.net/21.15107/rcub_grafar_748
Đorđević D, Stojnić I. On the combined effect of bed elevation discordances in the main-river and the tributary in 90° straight-channel confluences. in River Flow - Proceedings of the International Conference on Fluvial Hydraulics, RIVER FLOW 2016. 2016;:1616-1625. https://hdl.handle.net/21.15107/rcub_grafar_748 .
Đorđević, Dejana, Stojnić, Ivan, "On the combined effect of bed elevation discordances in the main-river and the tributary in 90° straight-channel confluences" in River Flow - Proceedings of the International Conference on Fluvial Hydraulics, RIVER FLOW 2016 (2016):1616-1625, https://hdl.handle.net/21.15107/rcub_grafar_748 .