Response of current, temperature, and algae growth to thermal discharge in tidal environment

This paper is a numerical analysis on response of current, temperature, and algae growth to thermal discharge in tidal environment. Three-dimensional distribution of current, temperature, and dimensionless specific growth rate of Nannochloropsis oceanica was simulated, based on realizable k − ϵ model for turbulence closure, and a light-inhibition model for prediction of algae growth. Numerical results of temperature are in good agreement with experimental observations. Numerical results show that vertical position of trajectory, maximum velocity, and minimum dilution are subject to the distribution of power function for near field with distance to injector less than jet-penetrating length. The power exponent is a function of time for the vertical position of trajectory, while it keeps constant for the maximum velocity and minimum dilution. Numerical results also show that the dimensionless specific growth rate of N. oceanica does not change with temperature rise monotonously, which implies that the distribution of temperature rise may not reflect to what extent does thermal discharge influence algae growth. The amplitude and phase of the dimensionless specific growth rate of N. oceanica change in the vertical direction, even for uniform and constant pH, nutrient concentration, and dissolved oxygen concentration.