Heat and mass transfer analysis of a counter flow cooling tower under various air and water flow arrangements

In this study the thermal performances of a forced draft counter flow wet cooling tower is experimentally investigated. Air and water are used as working fluids and the experimental runs are carried out by the air and water mass flow rate ranging between 0.017 and 0.064 kg/s, and between 0.03 and 0.05 kg/s, respectively. The inlet air wet bulb temperature at 23 °C, and water inlet temperatures are between 38 and 47 °C. The factors effecting cooling tower performance such as water inlet and outlet temperatures, air and water mass flow rates, heat load, and effectiveness of the cooling tower are investigated. The effect of the different air and water mass flow rates on water inlet and outlet temperatures are discussed. The effect of air mass flow rate on approach and range of the cooling tower, for different water mass flow rates are investigated. The variation of air mass flow rate on pressure drop for different water mass flow rates is presented. Other cooling tower parameters are Merkel number (Me) and number of transfer unit (NTU) to analyze the cooling tower performance. The number of transfer units (NTU) and Merkel number show the heat transfer capability of the cooling tower. Cooling tower effectiveness (?) relation with Merkel number for different air and water mass flow rates are calculated and all the results are presented in the form of graphs. The results show that cooling tower performance increases with an increase in air mass flow rate.