ABSTRACT
This article examined the energetic and exergetic performance evaluations of a computerized refrigeration cycle test rig for different concentrations of (CuO-Al2O3/MO) hybrid nano-lubricants and R600a refrigerant mass charges. In this particular investigation, three different refrigerant mass charges of 80 g, 100 g, and 120 g were employed, together with four different hybrid nano-lubricant concentrations of 0.1 g/L, 0.2 g/L, 0.3 g/L, and 0.4 g/L. A number of significant parameters, including COP, compressor power consumption (W), refrigerator pull-down time (minutes), second law efficiency (%), and total exergy destruction (W) of mineral oil without nanoparticles and nano-doped mineral oil using (CuO/Al2O3) hybrid nanoparticles as the lubricant, were examined in the course of this investigation. The optimum condition is achieved at 0.2 g/L of (CuO-Al2O3/MO) with 100 g mass of R600a refrigerant. At optimal conditions (0.2 g/L concentration of hybrid nano-lubricant and 80 g refrigerant mass charge), compressor work and total exergy destruction are lowered by (2.20–23.53%) and (4.51–49.00%), respectively. It is also observed that at optimum condition COP and second law efficiency grew within the range of (0.93–28.97%) and (3.38 to 25.42%), respectively. In conclusion, the performance of the computerized refrigeration cycle test rig altered with (CuO-Al2O3/MO) hybrid nano-lubricant concentrations and R600a refrigerant charges.
Nomenclature
CuO | = | copper oxide |
Al2O3 | = | aluminum oxide |
MO | = | mineral oil |
VCR | = | vapor compression refrigeration |
COP | = | coefficient of performance |
η2 | = | second law efficiency |
s | = | specific entropy |
Te | = | evaporator temperature |
Tc | = | condenser temperature |
To | = | ambient temperature |
ΔSgen | = | entropy generation |
ΔSsys | = | entropy change |
Itotal | = | total exergy destroyed |
Wcomp | = | input power or compressor work |
XRD | = | X-Ray diffraction |
Acknowledgements
We are grateful to the Maulana Azad National Institute of Technology, Bhopal, for providing the resources required to complete this research
Disclosure statement
The authors state that they have no known financial or interpersonal conflicts that would have affected the research presented in this study.
Additional information
Notes on contributors
Ankit Kumar
Ankit Kumar is a Ph.D scholar in mechanical engineering department at MANIT, Bhopal (INDIA). He works in the area of thermal engineering and refrigeration and air-conditioning.
Satish Pal Singh Rajput
Dr. Satish Pal Singh Rajput is a professor in mechanical engineering department at MANIT, Bhopal (INDIA). He works in the area of thermal engineering, refrigeration and air-conditioning, energy conversion cycles and human thermal comfort.