Influence of model mangrove trees on the hydrodynamics in a flume

The additional resistance created by mangrove model trees was investigated through experiments in a hydraulic flume and twodimensional depth-integrated numerical modelling. The numerical model reproduced the influence of the model trees and stilt roots for a range of flow conditions and experimental configurations after including a refined expression for drag on cylinders and the porosity effect. Drag coefficient values obtained from calibrating the hydrodynamic model with the experimental data ranged from 0 to 4.5. The results suggest that the drag coefficient may increase with increasing tree surface, but more data would be required to confirm this relationship. Simultaneous calibration of the drag coefficient and the eddy viscosity coefficient would improve the numerical model further.