abstract
modeling the friction effects of eelgrass
on the tidal flow in great bay, nh
by
Safak Nur Erturk
University of New Hampshire, May, 2000
In this study the frictional effects of eelgrass (Zostera marina L.) on the tidal flow in Great Bay, NH is modeled using a bottom friction coefficient adjustment approach. A two-dimensional, non-linear, time stepping, finite element model, ADAM is used. ADAM model incorporates two-dimensional wave physics, with a porous medium beneath the sediment surface to simulate wetting and drying process on the tidal flats. The effectiveness of ADAM model in simulating the tidal flow in Great Bay with wetting and drying on the tidal flats is verified. The model is calibrated by adjusting the bottom friction coefficient for the M2, M2S2 and M2S2N2 tidal forcing, respectively. Eelgrass beds are treated as extra dampers and higher bottom friction coefficient values are applied over the eelgrass beds. Addition of eelgrass to the area reduced the velocities over the eelgrass beds, increased the velocities in the channels, increased the water surface area at low water by holding more water.