Heat and mass transfer correlations for the design of small indirect contact cooling towers

Cooling towers are increasingly used in buildings as a component of environmental cooling systems. When compared with industrial towers, cooling towers with lower capacities and smaller dimensions can be used for this application, with inlet water temperatures ranging from 22 to 25 °C. Correlations for heat and mass transfer coefficients were obtained experimentally for a small-size indirect cooling tower, with a nominal cooling capacity of 10 kW. A detailed analysis of the mass transfer coefficient and spray heat transfer coefficient correlations is made, including the effect of the error in their evaluation on tower efficiency. The new correlations are compared with existing ones and results of their application to a simplified cooling tower model are shown.