ТHERMODYNAMIC PROPERTIES OF ISOBUTANE/MINERAL COMPRESSOR OIL AND ISOBUTANE/MINERAL COMPRESSOR OIL/FULLERENES C60 SOLUTIONS

ABSTRACT In present study a new experimental data for the saturated liquid density and saturated vapor pressure along the boiling line for the solutions of the ”natural” refrigerant isobutane (R600a) with mineral compressor oil and solutions of R600a/compressor oil/fullerenes C 60 is presented. Moreover, a new experimental data on the specific isobaric heat capacity, enthalpy and entropy along the boiling line for the R600a/compressor oil solutions is reported. Experimental data of the two-phase isochoric heat capacity was obtained for different compressor oil fraction in the refrigerant in the temperature range from 260 to 330 K. Obtained information was used to calculate the caloric properties of the R600a/compressor oil solutions. In addition, an influence of fullerene C 60 on the specific isobaric heat capacity of mineral oil was examined. The measurements of the heat capacity for the R600a/compressor oil solutions, pure compressor oil and compressor oil containing fullerenes C 60 were performed using an experimental setup that implements a direct heating method in adiabatic calorimeter. In addition, the heat capacity of oil and oil containing fullerenes C 60 have been measured using differential scanning calorimetry. Finally, the heat capacity increase for the compressor oil with the additives of 0.0020 kg•kg −1 of fullerenes C 60 was observed.