Performance investigation of vapor compression refrigeration system using R134a and R600a refrigerants and Al2O3 nanoparticle based suspension

Abstract

The improvement in performance parameters of refrigeration system using nanofluid has been investigated intensively for many years. The compatibility, stability and feasibility of nanofluid in refrigeration system have been quite challenging. The present experimental work involves the performance of Al2O3 nanoparticle based nanofluid in a vapor compression refrigeration system. The average diameter of 35 nm of Al2O3 nanoparticle with near-spherical morphology used for the experimentation. The lubricant oil of compressors has taken as the base fluid for the synthesis of Al2O3 nanofluid. The nanofluid has synthesized in the experiment of mass fractions of 0.02 wt%, 0.04 wt%, 0.07 wt%, and 0.1 wt% of Al2O3 nanoparticles. Two different types of refrigerant which are synthetic refrigerant (R134a) and hydrocarbon refrigerant (R600a) have used separately for the investigation. The polyester oil (POE) for R134a refrigerant and mineral oil for R600a refrigerant is incorporated in the experimental test rig. The coefficient of performance (C.O.P.), power consumption, compressor discharge pressure, evaporator pressure, and pull-down time were considered as performance parameters for the investigation of the vapor compression refrigeration test rig. The experimental results showed that by using 0.1 wt% of R600a-MO-Al2O3 mixture improves the C.O.P. by 37.2%, reduction in power consumption by 28.7%, increment in compressor discharge pressure by 8.9%, lowered evaporator pressure by 24.7%, and lowered the pull-down time by 17.6% compared to the conventional refrigeration system.