Flood-tide interaction numerical simulation at Min River tidal reach

Flood and tide features atMin River tidal reach are analyzed anda high-resolution flood-tide coupled model which useshigh-resolution GIS data for Minjiang Estuary with the highest grid resolution of 50-100m at key areas isestablished in this paper. Unstructured triangular mesh that can realize the grid resolution of 50-100m at key areas is employed in the model. Zhuqi section is chosen for flood boundary, and three numerical experimentsare conducted for June 6 2006 flood process. The experimental results indicate that, when coupled with tide and flood, the simulation of each tide gauge agrees very well with measured data compared withmodelresults only with flood or tide, and the original tidal features are changedat the different sections in Min River tidal reachedby the flood signals. Obvious flood characteristics are shown in Wenshanli and Jiefang Bridge station and flood-tidal mixed characteristics are shown in Xianan, Baiyantan and Guantou station.The strong interaction between tide and floodoccursin the watercourse (from Xiannan in South Channel to Guantou) because the current velocity is reduced during high water time but increasedduringlow water time.