Bed morphology is the result of a dynamic response to a complex meandering river system. It is an important factor for the further development of river. Based on the meandering river characterized by a large depth-to-...Bed morphology is the result of a dynamic response to a complex meandering river system. It is an important factor for the further development of river. Based on the meandering river characterized by a large depth-to-width ratio, a theoretical model is established with the coupling of Navier-Stokes （N-S）~ sediment transport, and bed deformation equations. The flow characteristics and bed response of river are obtained with the perturbation method. The research results show that, under the effect of two- dimensional flow disturbance, the bars and pools present the regular response. For a given sinuousness, the amplitude of the bed response can be used as a criterion to judge the bedform stability. The effects of the Reynolds number, disturbance wavenumber, sinuousness, and bed morphology gradient on the bed response development are described.展开更多
Through the fixed bed and live bed experiments, the factors influencing the turbulent width around bridge piers were analyzed, including approaching flow velocity, flow depth, flow angle, size of piers, shape of piers...Through the fixed bed and live bed experiments, the factors influencing the turbulent width around bridge piers were analyzed, including approaching flow velocity, flow depth, flow angle, size of piers, shape of piers and scouring. The experiments demonstrated that the turbulent width increased with approaching flow velocity, water depth and size of piers, kept constant with different flow angles, decreased as the shape of piers became smoother, and was less remarkably influenced by the scouring. Through applying the dimensional analysis method, the empirical expression was developed to calculate the turbulent width around bridge piers.展开更多
The distribution of velocity is one of the basic issues in river dynamics.Based on the experimental data measured by ADV in the flume of State Key Hydraulics Laboratory (SKHL),this paper analyzed the ver- tical distri...The distribution of velocity is one of the basic issues in river dynamics.Based on the experimental data measured by ADV in the flume of State Key Hydraulics Laboratory (SKHL),this paper analyzed the ver- tical distribution of point velocity and the varying law of turbulence intensity in straight mobile compound chan- nel with an asymmetric floodplain.Above certain relative height,the streamwise point velocity follows the loga- rithmic distribution.Below the location,the velocity varies linearly approxim...展开更多
文摘Bed morphology is the result of a dynamic response to a complex meandering river system. It is an important factor for the further development of river. Based on the meandering river characterized by a large depth-to-width ratio, a theoretical model is established with the coupling of Navier-Stokes （N-S）~ sediment transport, and bed deformation equations. The flow characteristics and bed response of river are obtained with the perturbation method. The research results show that, under the effect of two- dimensional flow disturbance, the bars and pools present the regular response. For a given sinuousness, the amplitude of the bed response can be used as a criterion to judge the bedform stability. The effects of the Reynolds number, disturbance wavenumber, sinuousness, and bed morphology gradient on the bed response development are described.
基金National West Communication Construction Technology Project (No.200432800040)
文摘Through the fixed bed and live bed experiments, the factors influencing the turbulent width around bridge piers were analyzed, including approaching flow velocity, flow depth, flow angle, size of piers, shape of piers and scouring. The experiments demonstrated that the turbulent width increased with approaching flow velocity, water depth and size of piers, kept constant with different flow angles, decreased as the shape of piers became smoother, and was less remarkably influenced by the scouring. Through applying the dimensional analysis method, the empirical expression was developed to calculate the turbulent width around bridge piers.
基金Supported by Key Project of Chinese.Ministry of Education (03134)
文摘The distribution of velocity is one of the basic issues in river dynamics.Based on the experimental data measured by ADV in the flume of State Key Hydraulics Laboratory (SKHL),this paper analyzed the ver- tical distribution of point velocity and the varying law of turbulence intensity in straight mobile compound chan- nel with an asymmetric floodplain.Above certain relative height,the streamwise point velocity follows the loga- rithmic distribution.Below the location,the velocity varies linearly approxim...
