Modeling Bed Load Transport through Vegetated Channels Using Conceptual Pseudo Fluid Model

Document Type : Research Paper


Assistant Professor, Department of Water Engineering, Faculty of Agriculture, Vali-e-Asr University of Rafsanjan, Rafsanjan, Iran,


Bed load transport modeling in rivers and channels with vegetation over bed and banks is important. On the other hand, the complexity of bed load transport through vegetation and shortcoming of previous studies, declare the necessity of developing new models. Therefore, in the present study, the pseudo fluid model in combination with bed shear stress and resistance equation was used based on stochastic method of bed load transport. The developed model uses new definitions for dimensionless parameters of flow intensity and bed load rate that include vegetation properties with fluid and sediments. The calibration and verification of model results with experimental results showed that the model with R2=0.91 and RMSE=8.2 have accurate capability in modelling bed load transport through vegetation. The parametric analysis of vegetation features and comparing the results with previous equations showed the reduction of 45 and 68 % in absolute mean error in Mayer-Peter-Muler (R2=0.45,  RMSE=231.9) and Parker (R2=0.75,  RMSE=91.9) models, which indicates the superiority of developed model and the presented framework can be used in hydraulic analysis of sedimentation engineering in rivers.


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