Experimental and analytical study of the energy and exergy performance for different evaporative pads in hot and dry climate

Abstract

In this work, effects of using different evaporative cooling pads (ECPs) on the energetic and exergetic efficiency of a direct evaporative air cooler (DEAC) have been theoretically and experimentally investigated. Three types of ECPs were used, i.e., honeycomb cellulose cooler pad (HCCP), shading-cloth cooler pad (SCCP), and aspen wood wool cooler pad (AWWCP). For SCCP and AWWCP, a 3-cm pad thickness was used, while for the HCCP, three different values of pad thickness were used, i.e., 3, 5, and 7 cm. Tests were carried out using air velocities of 8, 14, and 19 m/s, measured at the DEAC outlet. Engineering equation solver (EES) used for performing the required calculations of the various parameters affecting the thermal performance of the DEAC, i.e., dry bulb temperature at exit (Tdbo), relative humidity at exit (RHo), mass of water evaporated, saturation efficiency, energetic efficiency (ηen), exergetic efficiency (ηex), and the overall exergetic efficiency (ηexoverall). Results showed the great effectiveness of HCCP compared to the other studied types. HCCP showed the highest energetic efficiency reached 103 % for 3 cm thickness of the ECP, and the highest exergetic efficiency of about 19 %. All with the highest temperature difference, achieving 10.3 °C.

Keywords

• Evaporative cooling
• Energy efficiency
• Exergy efficiency
• Cooling pads
• Saturation efficiency