EFFECTIVENESS OF CROSS-FLOW PLATE HEAT-EXCHANGER FOR INDIRECT EVAPORATIVE COOLING

A short-cut method for calculating the effectiveness of wet surface cr ossflow plate heat exchangers is developed. It introduces a correction for the effectiveness estimated according to the method of Maclaine-c ross and Banks. For this purpose a new model with a water film that fl ows down, corresponding to the real conditions in these heat exchanger s, is developed. The method of Maclaine-cross and Banks is improved by an approach to determine the mean water surface temperature and by de rivation of an equation for calculating the ratio of total to sensible heat taking into account the barometric pressure. Performance predict ions by this method for wet surface crossflow prate heat exchangers ar e found to agree with the finite difference solutions. (C) 1998 Elsevi er Science Ltd and IIR. All rights reserved.