Increasing the thermal performance of cooling tower by utilizing swirling jets

Abstract

Cooling towers are generally utilized in heating, ventilation, and air conditioning systems, electric power plants and manufacturing applications. The main problem for cooling towers is evaporation loss. The evaporation loss is decreased with utilizing fans, drift eliminators for more water saving. This work is mainly focused numerical analysis of cooling tower for reducing evaporation loss and increase the efficiency of the tower by utilizing two crosswise swirling jets that reduce the inlet hot water temperature in the outlet of the cylindrical channel to the not harmful to ambient conditions temperature. The model is computed for various parameters; air inlet temperatures (10, 22, 32, 40 °C) and Reynolds number for jets inlet velocities (Re= 3900, 5200, 7800, 8500). This model was studied numerically by utilizing ANSYS Fluent CFD software. In this work, it is achieved that increasing Reynolds number causes an increase on evaporation loss. The higher air inlet temperature causes higher evaporation loss. When the air inlet temperatures are reduced from 40 °C to 10 °C, the evaporation loss is decreased as 62% and 81%, respectively. When Reynolds number is decreased from 8500 to 3900, the evaporation loss decreased as 30%. By utilizing this new design, the outlet water temperature could be reduced of 19 °C. Moreover, the numerical findings were validated by some researches available in the literature.

Keywords

• Direct contact cooling,effectiveness,evaporation loss,swirling jet

References

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