Application of thermal plume modelling and establishment of initial mixing zone

The well known Brooks’ simple surface plume model ( Brooks, 1960 ) assumed a steady flow of constant speed. Such an assumption may not be true for nearshore coastal waters. An improved and more general surface plume model, without such a restriction, has been developed by the authors ( Chen and Thompson, 1995 ). Further improvement and refinement to the model have been made to include diffusion effects in the vertical direction. A surface thermal discharge study has been carried out using the refined surface plume model for a proposed coastal thermal discharge scheme. It has been shown that an initial mixing zone near the outfall discharge can be established for a given temperature rise threshold value by varying the cross-current speed and direction. A number of sensitivity tests were also carried out, including for example diffusion coefficients, surface heat exchange coefficient and the variations in ambient cross-current.