Estimation of Wave Force Coefficients on Mangrove Models

Abstract

An experimental study of water waves through a model mangrove forest is presented in this paper. Instead of using idealized or artificial tree models, 3D-printed mangrove models whose geometric structure was based on a typical mature tree (Rhizophora apiculata) at a scale of 1/7 were adopted in the laboratory experiments. During the experiments, the fluid velocity and forces on the tree model were directly measured, which provided a comprehensive investigation of the wave-induced forces on mangroves under various wave conditions. Comparing the predicted forces by Morison-type formula1) with the experimentally-measured forces, good agreements were observed, indicating the proper estimations of drag and inertia coefficients. To provide a useful tool for the estimation of wave dissipation in the future model developments, the relationships between force (drag/inertia) coefficients and the flow parameters (i.e. Reynolds/Keulegan-Carpenter numbers) are presented.