Author(s): Shuyou Cao; Kejun Yang; Zhixiang Zhang; Xingnian Liu
Linked Author(s): Xingnian Liu, Kejun Yang
Keywords: Stage-discharge curve; Flow resistance; System dynamics model; Compound channels
Abstract: Stage-discharge curves are particularly important in river basin management. For a compound channel, the stage-discharge curve is often difficult to be extrapolated to yield estimates of level for a given frequency of flow. By undertaking the symmetric compound channel with large scale, the authors measured the stage-discharge curve for inbank and overbank flow. By analyzing the experimental data, it is found that the effective Manning’s coefficient approximately approaches to a constant in a single channel after water depth is larger than certain value. Otherwise, when water in main channel flows out of bank, the effective Manning’s coefficient abruptly decreases corresponding to the decreasing of hydraulic radius. Afterwards, it increases with flow depth increasing. For the non-linear complex behavior, the authors based on the resistance coefficient relationships obtained, applied system dynamics method and established the system dynamics model of conveyance capacity for overbank flow. The model gives the relationship between stage and discharge. The computed result shows that there is a good agreement with modeled and experimental values.
Year: 2005