Numerical Research of Temperature Rise in Xiangshan-Harbor Estuary

Temperature rise in Xiangshan-Harbor estuary caused by plants' thermal water discharging is numerically studied by using three-dimensional ocean model FVCOM. A surface heat flux calculating method is introduced into the model, in which diurnal and seasonal variation of solar radiation is considered to better describe the heat exchange between sea and air. The temperature rise field is then calculated as the difference between temperature fields of two numerical experiments, one with thermal water discharging, and the other without. The initial temperature field is set to the monthly average for many years, which is more reasonable than uniform field. Discharging temperature is set to water intake temperature plus specific temperature rise from the plant, which includes the impact from the temperature rise of water intake. Validations of current velocity, current direction, elevation, and temperature prove the model. Model results show that the temperature rise is mainly distributed around the discharging outlet. It spreads significantly wider at water surface than at bottom. At Guohua Plant, due to more discharging amount in summer, temperature rise area is greatly larger than in winter. At Wushashan Plant, the difference between summer and winter is small because of the constant discharging amount.