Effect of hybrid and single nanofluids on the performance characteristics of chilled water air conditioning system. (25th December 2019)

• Record Type: Journal Article
• Authors: Ahmed, M. Salem; Elsaid, Ashraf Mimi
• Is Part Of: Applied thermal engineering. Volume 163(2019)
• Publication Date: 2019-12-25
• Subjects: Hybrid nanofluids -- Air conditioning -- Chilled water -- Nanoparticle -- Al2O3 -- TiO2; Heat engineering -- Periodicals; Heating -- Equipment and supplies -- Periodicals; Periodicals; 621.40205
• DOI: 10.1016/j.applthermaleng.2019.114398
• Languages: English
• ISSNs: 1359-4311

Abstract

Highlights: Performance analysis of vapor compression chiller utilizing hybrid and single nanofluids is investigated. A comparison between nanofluids, hybrid nanofluids, and pure water is analyzed. Compression ratio and compressor work are evaluated under different concentrations of hybrid and single nanofluids. The maximum COP occurs at a single nanofluid of Al2 O3 /H2 O. Single nanofluid Al2 O3 /H2 O provides a lower compression ratio than TiO2 /H2 O. Abstract: In this work, the performance characteristics of a vapor compression refrigeration system associated with a chilled water air conditioning unit utilized nanofluids (Al2 O3, TiO2, and a hybrid of Al2 O3 /TiO2 based H2 O) were experimentally investigated. The tested parameters were; nanoparticle concentration, nanoparticle type, nanofluid flow rate, nanoparticle hybridization ratios, and air velocity. The study incorporated different concentration ratios of nanoparticles 0.05, 0.1, 0.2, 0.3, 0.4, 0.6 and 1% for Al2 O3 /H2 O whereas 0.1, 0.3, 0.4, 0.6 and 1% for TiO2 /H2 O. Five different concentrations of hybrid nanoparticles Al2 O3 /TiO2 were employed by 0.1/0.1, 0.2/0.1, 0.3/0.1, 0.3/0.2 and 0.3/0.3 wt%. Experiments were done at air velocity ranging 0.61–1.9 m/s whilst the fluid flow rate was varied by 0.12–0.3 m 3 /s. Experimental results indicated that the single nanofluid of Al2 O3 /H2 O contributed a higher coefficient of performance and a lower elapsed time for cooling the fluid of a chiller system. Higher values of the VCRS coefficient of performance were obtained at lower values of air velocity of air conditioner and higher values of the nanofluid flow rate of the chiller unit. The Al2 O3/H2 O provided lower values of compression ratio and higher values of the refrigeration effect in comparison with TiO2 /H2 O by approximately 4.1% and 5.3%, respectively.