Numerical modelling of hydrodynamics and sediment transport processes during storm events in a non-perennial river This article presents the numerical modelling of hydrodynamics and sediment ...transport processes in the seasonal Pathri Rao River, which flows in the Northern part of India. Modelling is made by the coupled application of the hydrodynamic model called TELEMAC-2D and the morphodynamic model called SediMorph. The hydrodynamic model results are validated with the observed data and it has been found that the present model provides reasonable predictions. Likewise, the validation of the morphodynamic model is also presented. For this purpose, the suspended and bed load transport modules are validated separately for four runoff events observed during the investigations. The validation of the former is approached by comparing the depth-averaged suspended transport concentrations against experimental measurements made at the make-shift gauging station and subsequent comparison against experimental measurements. On the other hand, due to non-availability of the observed values on bed load sediment transport, the bed load sediment transport and bed evolution numerical results could not be validated quantitatively and was approached only on qualitative basis. In general, both validations present an acceptable agreement with measurements and scientific facts. Further, this study demonstrates that the coupled TELEMAC-2D/SediMorph system could be used with confidence for practical applications in the Pathri Rao River.
Incipient motion is the critical condition at which bed particles begin to move. Existing relationships for incipient motion prediction do not consider the effect of seepage. Incipient motion design ...of an alluvial channel affected from seepage requires the information about five basic parameters, i.e., particle size d, water depth y, energy slope Sf, seepage velocity vs and average velocity u. As the process is extremely complex, getting deterministic or analytical form of process phenomena is too difficult. Data mining technique, which is particularly useful in modeling processes about which adequate knowledge of the physics is limited, is presented here as a tool complimentary to model the incipient motion condition of alluvial channel at seepage. This article describes the radial basis function (RBF) network to predict the seepage velocity vs and average velocity u based on experimental data of incipient condition. The prediction capability of model has been found satisfactory and methodology to use the model is also presented. It has been found that model predicts the phenomena very well. With the help of the RBF network, design curves have been presented for designing the alluvial channel when it is affected by seepage.
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