Abstract
A numerical study is conducted to simulate flow and heat transfer in shallow cooling ponds. A depth-integrated CFD model, based on the finite-volume method, is developed and applied to calculate detailed velocity and temperature distributions inside the pond. The numerical model is validated by comparing results with temperature measurements available for an experimental cooling pond. The model is used to investigate effect of mass flow rate (m) on pond hydrodynamics and thermal characteristics for cases of without and with internal baffles. The results show that the pressure loss coefficient remains constant, while the pressure drop between pond inlet and outlet increases with increasing m. The heat dissipated from the pond at the air-water interface increases with m despite the decrease in difference between water inlet and outlet temperatures. The pond effective heat-transfer coefficient, pond mean temperature, and water loss by evaporation are determined as a function of m. and relative humidity. The outlet temperature from the pond is determined as a function of pond cooling capacity. Streamline plots show that the flow pattern is independent of m but is strongly dependent on geometric configuration. A single contour map of normalized speed is, therefore, sufficient to describe all speeds inside the pond for different m. It is recommended that m should be as high as possible in order to enhance heat transfer from the pond but this would increase pumping power of cooling water through condenser tubes in which a compromise must be sought.