Experimental investigation of fill pack impact on thermal-hydraulic performance of evaporative cooling tower

The present work deals with an experimental study of the performance of an evaporative cooling tower (ECT) with a developed fill pack. The fill pack consists of inclined-corrugated contact elements (ICCE) made of the metal plates with perforations, providing a uniform distribution of interacting phases over the ECT cross-sectional area. This study investigates the effect of fill pack design on hydraulic and thermal characteristics of the ECT. Four empirical equations were found for the pressure drop through four types of dry fill packs. The detailed analysis includes two fill packs consisting of ICCE with 6 mm holes with and without a metal grid. Hydraulic operating regimes of the ECT and empirical equations for the wetting pressure drop through the fill packs had been defined. Based on experimental data and the method of transfer units, empirical relationships of the volumetric mass transfer coefficients were determined. The comparison between the obtained results and those found in the literature for other types of proves the high performance of the developed fill packs. Besides, using the Lewis relation, the dependencies of the volumetric heat transfer coefficient on the average air velocity were analyzed. The results indicate that maximum cooling efficiency of the studied fill packs was observed at the low wetting rates according to the Merkel number. The fill pack from ICCE with 6 mm holes and without the metal grid seems to be more efficient, as it provides relatively higher values of the heat and mass transfer coefficient and lower pressure drop.