Effect of Confluence Ratio Change on Hydrodynamic Character in Reservoir Area

Abstract:

Major factors that affect hydrodynamic character include confluence ratio, junction angle, bed discordance and channel gradient. In reservoir area, the river confluence is also affected by change of water level results from impoundment. Focused on asymmetrical confluence with 90° junction angle in reservoir area and based on model test, velocity distribution, location and range of reverse flow zone under different confluence ratios and water levels were investigated. The results show that flow velocity always declined along the channel after convergence. When confluence ratio increased, velocity decline rate accelerated, tributary flow diffused more fiercely at the conflux section, reverse flow zone enlarged. As the water level rising up, overall flow field velocity was weakened, the degree of tributary deflection increased. The velocity declined much slower in high water level.

• Periodical: Applied Mechanics and Materials (Volumes 438-439)
• Pages: 1303-1308
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.438-439.1303
• Online since: October 2013
• Authors: Tao Yan, Li Chen, Tao Duan, Min Zhou
• Keywords: Confluence Ratio, Hydrodynamic Character, Model Test, Reservoir Area, River Confluence

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