Experimental and normalized sensitivity based numerical analyses of a novel humidifier-assisted highly efficient indirect evaporative cooler
Muhammad Ahmad Jamil, Ben Bin Xu, Laurent Dala, Muhammad Sultan, Lin Jie, Muhammad Wakil Shahzad
Abstract
Indirect evaporative cooling technology has emerged as an energy-efficient, low-cost, and sustainable alternative to conventional air conditioning systems for space cooling. This is because of its significant (40–50%) energy-saving potential compared to ventilation, vapor compression cooling, and desiccant cooling systems. The current paper presents a novel humidifier-assisted regenerative indirect evaporative cooler that eliminates the use of hydrophilic surfaces within the system and mitigates the fouling propensity and water management issues. A generic cell of the proposed system is fabricated and tested for different operating scenarios along with the uncertainty propagation analysis. Thereafter, a normalized sensitivity analysis is performed to identify the most influential parameters on the cooler performance. The experimental data shows an effective cooling performance with a temperature drop of 20 °C of outdoor air and cooling capacity of 175 watts of 1800 mm × 300 mm generic cell. The cooling coefficient of performance was calculated as 44 and maximum effectiveness of 83.82% for the proposed configuration. The sensitivity analysis reveals scaling trends of the coefficient of performance in the following order of primary air inlet temperature > primary air outlet temperature > primary air velocity and the cooler effectiveness as secondary air outlet temperature > primary air inlet temperature > primary air humidity > primary air outlet.