Evaluation of the properties of POE/SiO2 nanolubricant for an energy-efficient refrigeration system – An experimental assessment

The effect of silica nanoparticle on thermal, chemical, corrosive, and the nature‐friendly properties of refrigerant compressor lubricants—A comparative study

“…The stability of the synthesized nanolubricant is quantified at room temperature, by means of the rate of absorbance of the UV–Vis spectrum using a spectrophotometer during the first and sixth day after preparation (Figure 5a). The maximum absorbance attained for the Min/SiO 2 nanolubricant (0.20%) was 0.184 at 216.010 nm during the first day and was 0.152 at 216.999 nm at the end of the sixth day after synthesis, and corresponding values for the POE/SiO 2 34 nanolubricant (0.2%) were 0.893 at 216.999 nm and 0.768 at 216.999 nm.…”

“…Thighest value of thermal conductivity ratio for Min/SiO 2 nanolubricant was 1.077, and that is 7.75% higher than that of the base Min oil thermal conductivity. The corresponding highest value of thermal conductivity ratio for POE/SiO 2 34 nanolubricant is 1.109, and it is about 10.95% higher than the thermal conductivity of the base POE oil. Both these highest values are obtained for a SiO 2 mass proportion of 0.2%, and the lubricant temperature of 85°C, respectively.…”

“…To statistically validate the thermal conductivity values of the Min oil and POE oil nanolubricant, a response surface methodology (RSM) (using Design Expert, a statistical software), was used. The regression equation of the developed model is given in Equations (Min/SiO 2 nanolubricant) and () (POE/SiO 2 nanolubricant 34 ). The regression Model's F value of 42.63, a p value of <0.05, the lack of fit F value of 4.96 in case of Min/SiO 2 nanolubricant (Table 2), and corresponding values for POE nanolubricant which are 68.61, <0.05, and 1.95 (Table 3) clearly show that the model and terms in the model are significant for both the cases, and therefore, it is statistically validated.…”

“…Here, for the synthesis of nanolubricants, surfactant was not used. Figure 1b shows the structural property, analyzed using X‐ray diffraction (XRD), and it can be identified as a crystalline structure since the result resembles with the COD ID 9013493 34,38 . POE and Min oil nanolubricants with five mass concentration (Figure 2) were taken for the study (0.01, 0.05, 0.1, 0.15, and 0.2 mass%).…”

“…This paper hence experimentally investigates and compares the thermal conductivity along with the other thermal properties, corrosive nature, chemical stability, and eco‐friendly properties of Min oil (ISO VG 46) and compares it with the available data of polyolester (POE) oil (ISO VG 68) 34 suspended with the same mass proportions of SiO 2 nanoparticles. The effect of particle mass concentration on the thermal conductivity was also examined at wide temperature ranges.…”