THERMAL CHARACTERISTICS INVESTIGATION OF NATURAL DRAFT HYBRID (WET/DRY) COOLING TOWER

This study aims to analyse heat transfer mechanisms between water and air via direct contact (wet section) and indirect contact (dry section) in a natural draft hybrid cooling tower model. A prototype has been constructed based on geometrical, dynamic, and thermodynamic similarities to imitate a natural draft hybrid (wet/dry) cooling tower using natural draft hybrid technology. The experimental tests were carried out in summer (hot and dry) weather in accordance with Iraqi meteorological conditions, with splash fill packing measuring 15cm in height. This study aims to determine the influence of water flow rates and air flow rates on the cooling range, relative humidity, cooling capacity, and overall efficacy of a cooling tower. The experimental tests were carried out using four different water flow rates ranging from 7.5 to 12.0l/min and six different air velocities ranging from 0.4 to 2.4m/s while maintaining the intake water temperature constant 55ºC and the crosswind constant at zero (m/s). As a consequence of the experiments, it was discovered that the water mass flow rate and air velocity impacted all of the factors discussed earlier in varying degrees.