Crosswind influence on heat and mass transfer performance for wet cooling tower equipped with an axial fan

Abstract

To enhance the thermal performance and relieve the impact of crosswind on the super large-scale natural draft wet cooling towers (SLWCTs), based on our previous research, through the three-dimensional numerical simulation of the SLWCT equipped with an axial fan, the impact of the fan positions on the thermal performance was investigated at various crosswind velocities (1–9 m/s) when the fan power was fixed to 200 kW. It is obtained that the optimized fan diameter and the installation height are 20 m and 18 m. Additionally, the characteristics of the aerodynamic and temperature field inside the tower with different fan positions were discussed based on the above results, subsequently, the change rules of water temperature drop, evaporation loss, and heat transfer coefficient are analyzed. The results manifested that the optimization scheme efficiently relieves the adverse effects of the crosswind, and the air velocity near the fan is significantly increased. By comparison with the case of no fan, the heat transfer coefficient and water temperature drop increase by 4.79% and 0.226 °C, respectively, and the evaporation loss increases by 2.86% at the utmost.

Keywords

• Super large-scale wet cooling towers
• Water dropping potential energy
• Forced ventilation
• Crosswind effects
• Thermal performance