Numerical investigation & CFD analysis of cooling tower at varying inlet flow directions.

A cooling tower is a heat rejection structure that releases waste heat into the atmosphere by lowering the temperature of a water stream. All heat-producing industries use cooling towers for cooling the water for re-circulation in the powerplant. The rectangular and circular cooling towers are the two widely used types employed in many industries. This work is focused on re-creating an induced draught cooling tower taken from industrial powerplant, which is circular in cross-section. A CFD analysis of cooling tower is carried out using ANSYS Fluent which is equipped with fan at the top allowing hot air to escape while pulling air throughout the cooling tower. The cooling tower performance was investigated in this study by calculating the effectiveness and evaporation capacities by varying air inlet angles. The cooling tower under consideration is re-created primarily for small scale industries. The modelling of the tower is done by considering industrial design aspects and dimensions taken from an existing thermal powerplant. The heat exchange that is taking place inside the cooling tower is visualized where temperature contours are studied carefully for various arrangements of air inlets. These arrangements are usually flat and inclined air inlets having inclinations at 30° with respect to vertical and horizontal axes. A cooling tower model with air inlet arranged at 30° inclined to both vertical and horizontal axes resulted in higher heat exchange rates with temperature drop of hot water upto 22°C. A validation with theoretically calculated evaporation capacities is made and comparison of the same is done. [ABSTRACT FROM AUTHOR]