One-Dimensional Numerical Simulation On Compound Channel

Compound open channel flows widely exist in nature in our country, and these carry the total discharge by the main channel and the floodplains in the flood period. Recently, the sedimentation is more and more serious and it is not easy to carry flood because of the natural reasons and man's activity, so that flood disasters is often occured, and this imperils the property even life of people. Then some structural measures are exactly performed. On the other hand, levees are often rebuilt or realigned to increase flood control standard and make best utilization of the floodplains going with rapidly increasing of the population and the request of the urban lanscape. All these works are related to the questions of the computation of discharge capacity and the determination of the flood levels. Although respectable fruits are got at present, the limitation in the practicability and applicability also exist. So the study of the work is significant to the flood management and river control.The previous research works are reviewed and summarized in this paper. Actual research methods of the one-dimensional compound channel are classified and compared on the base of whether take into account the apparent shear stress between the main channel and the floodplain, and got the conclusion that the means with the apparent shear stress can get a high precison but isn't suit for the pratical engineering, and the means without the apparent shear stress is simple and practical but its precison is low.The text choose the method without consideration the apparent shear stress,and depending on the ratio of velocity of the floodplain and the main channel, approcimate area method and average velocity method are used. Pressimann four-point linear implicit scheme are selected to dissipate St.venant equations to got algebra equations, and then water hydrodynamic conditions prediction model is eatablished.Acting at the key effect of the roughness coefficient in the hydrodynamic conditions prediction model,the SVD method is introduced to eatablished roughness coefficient calibrating model. Then DONGJIANG channel project is used to validate...