Gradually Varied Flow Computation in Series, Tree Type and Looped Compound Channel Networks


  • Ghulam Nabi
  • H. Reddy
  • Habib -ur- Rehman


The computations for compound channel section are difficult in most of the case when the channels are connected with each other in different forms such as tree type of looped network. The computation at the bifurcation points are difficult in the sense that change in discharge has to satisfy the continuity and momentum equations. In the iteration procedure the computations some time become unstable due to magnification of the error. . An algorithm is presented to compute the water surface profiles in steady, gradually varied flow of open channel having compound cross section. The methodology is more general and suitable for application to compound and trapezoidal channel cross sections. The algorithm is capable of calculation of water surface profiles in all types of channel network i.e., series channel, tree type network and looped network. In this method the energy and continuity equation are solved for steady, gradually varied flow computations. The Newton Raphson method has been used for the solution of resulting non linear equations. The results have verified with the physical model for channel network. The observed and computed results are in good agreement.


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Civil Engineering,Structures, Construction, Geo technology, Water, Transportation