Hydrodynamics of Wave and Current Vegetation Interaction

Abstract

Using flow equations for overflow region and force balance for vegetation region, a vertical two-dimensional incompressible combined flow field of waves, current, and submerged vegetation is mathematically formulated. Stream functions for these regions are separately derived using appropriate boundary conditions and extended for weak damping of waves in the direction of propagation. Both stream functions are coupled using the interface boundary condition to derive a mathematical model for the combined wave-current-vegetation flow field that provides insights into the combined flow structure for no-damping and damping cases. The internal wave at the interface (vegetation top) is also derived and found to be in phase with the surface wave. The dispersion relations explicit in wave frequency are derived for the following/opposing wave-current environment. The model is extended for the emergent vegetation case with wave damping. The proposed model is compatible and covers a wide range of hydrodynamic characteristics of wetland flows.