Performance enhancement studies on evaporative cooling using volumetric heat and mass transfer coefficients

In the present work, a test facility has been set up to observe direct water-air interaction with and without a cellulose cooling pad. Volumetric heat and mass transfer coefficients have been introduced to understand air-water interaction so that contact volume between air and water with and without pad can be used as an effective parameter in the analysis. Experimental values of these parameters have been determined and correlations for Nusselt and Sherwood number have been obtained with a maximum of +/- 20% error band. Also, a two dimensional, numerical model for water and air interaction in cross flow has been developed based on mass and energy balance as well as convective heat and mass transfer relations. Exit temperature and relative humidity of air, exit temperature of water measured from experiments are compared with those obtained from numerical model and the agreement is generally good with a maximum deviation of 15%.