An exponential-based model for predicting velocity fields in partially vegetated channels

A model based on the exponential function was proposed to predict the velocity fields in partially vegetated channels. Eleven groups of experimental data obtained from this study and the published literature were used to verify the model. The predicted lateral profiles of velocities at different longitudinal positions had good agreement with measurements over wide ranges of flow and vegetation conditions, indicating that the proposed model is capable of predicting the velocity fields in the complicated partially vegetated flows. Combining the proposed model with an existing model that predicts the critical velocity for initiating the resuspension of noncohesive sediment in vegetated regions defined the patch length that would be sufficient to promote sediment deposition within the patch interior. For a sparser patch or finer sediment, a longer patch is required to promote deposition and thus protect beds from erosion.