Flow Investigations in a Wide Meandering Compound Channel

Ext reme co mplexit ies present in flow behavior of meandering compound channels necessitate the study and analysis of such channels under different geometric and hydraulic condition to further our knowledge in understanding the dependency of flo w characteristics e.g. velocity, boundary shear etc. on d ifferent sectional parameters like width rat io, aspect ratio and hydraulic parameter such as relative depth. The present paper draws on our investigations on a meandering compound channel,where physical experiments were conducted on a smooth sine generated trapezoidal main channel flanked on both sides by wide flood plainsunder different relative depths. A 2dimensional hydrodynamic model CCHE2D and another quasi1D model Conveyance estimation System (CES) were then applied in turn to the same test cases to numerically investigate the flow in the co mpound meandering channel. The results of such investigations were then compared for validation purpose with observed experimental values of important flow parameters like depth averaged velocity and boundary shear distribution across the channel cross section. It is seen that CCHE2D is quite capable of producing results in agreement with their physical values and also it partly agrees with results of CES.It is expected that the results shown in this paper would enrich the research data base in the field of co mpound channels and help the scientists in using the numerical model CCHE2D, as a viable research tool in the field of river engineering.

[1]  CAROLINE MC GAHEY METHODOLOGY FOR CONVEYANCE ESTIMATION IN TWO-STAGE STRAIGHT, SKEWED AND MEANDERING CHANNELS , 2003 .

[2]  Howard H. Chang Energy Expenditure in Curved Open Channels , 1983 .

[3]  R. Sellin,et al.  Behaviour of meandering two-stage channels , 1993 .

[4]  Boundary shear stress distribution in meandering compound channel flow , 2007 .

[5]  G. Pender,et al.  Three-Dimensional Hydrodynamics of Meandering Compound Channels , 2002 .

[6]  G. H. Toebes,et al.  Hydraulics of Meandering Rivers with Flood Plains , 1967 .

[7]  V. C. Patel Calibration of the Preston tube and limitations on its use in pressure gradients , 1965, Journal of Fluid Mechanics.

[8]  D. Ervine,et al.  Experimental and computational aspects of overbank floodplain flow , 1987, Transactions of the Royal Society of Edinburgh: Earth Sciences.

[9]  K. Babaeyan-Koopaei,et al.  Two-Dimensional Solution for Straight and Meandering Overbank Flows , 2000 .

[10]  Hefang Jing,et al.  Three‐dimensional numerical simulation of compound meandering open channel flow by the Reynolds stress model , 2009 .

[11]  Y. Zech,et al.  Momentum transfer for practical flow computation in compound channels , 1999 .

[12]  R. Sellin,et al.  DEVELOPMENT OF A SIMPLE METHOD TO PREDICT DISCHARGES IN COMPOUND MEANDERING CHANNELS. , 1993 .

[13]  Smith Square Dean Stanley Reducing Uncertainty in River Flood Conveyance , 2003 .

[14]  Donald W. Knight,et al.  The SERC Flood Channel Facility , 1987 .

[15]  D. Knight,et al.  Stage-Discharge Assessment in Compound Meandering Channels , 1999 .