Evaporative coolers are three-fluid heat exchangers used to reject heat to the environment. A mixture of air and recirculating water is used as the cooling medium. In this paper, the heat and mass transfer processes taking place in a vertical-tube evaporative cooler are studied. A steady-state, one-dimensional model of cooler performance is formulated and is validated by experimental measurements, taken in a single-tube exchanger, of the controlling heat and mass transfer coefficients. These coefficients occur at the air-water interface. Heat fluxes and enhancement ratios for conditions of interest are measured and calculated, and the results are compared and discussed. The model is found to adequately predict heat exchanger performance.
