The Numerical Model Computation of Brine Dispersion for Taoyuan Seawater Desalination Plant

• Main Authors: Cheng-Lung Chen, 陳正龍
• Other Authors: Wen-Hen Yang
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/45254267500679221024

碩士 === 國立臺灣海洋大學 === 河海工程學系 === 101 === Since the population expands massively in Taoyuan, thus the government plans to build the seawater desalination plant which can supply the demand of fresh water. Yang and Ye (2012), did not consider the impact of the wind. Thus, this study adds the time series data of the wind as boundary condition, to simulate numerical results which closer to field data. This study uses numerical models MIKE 21 and MIKE 3 which developed by DHI. These numerical models consist of Hydrodynamic module (HD) and Advection-Dispersion module (AD).This study uses domain of M1 bathymetry and eight tidal constituents. By using harmonic analysis, this study can obtain the water level as the boundary conditions of the M1 hydrodynamic module. Preliminary judgment the M1 simulation is correct with measured tide. For a more accurate simulation, we extract water level boundary condition from the M1 hydrodynamic module, to simulate the middle computational domain M2. By using M2 simulation results, compare with observation field data in flow velocities and directions to calibrate computational parameters in reasonable agreement. The same as previous step, we also extract water level boundary condition from the M2 hydrodynamic module, to calculate the smallest computational domain M3. Then add advection-dispersion module (AD) to compute the effect on the flow current and salinity dispersion. According to the simulation results, the salinity of sea water after brine discharging is diluted rapidly in the layer of Z1. Even near the outfall area, the maximum salinity values are around 37 ~ 35 psu. At Z2 layer, the salinity values reduce to 33 ~ 34 psu. Over the Z3 layers, the salinity of sea water just higher than the background values of 0.03~0.05 psu which is no cumulative effect. The simulated numerical results are closer to field data, the accuracy of considerable credibility.