Thermodynamic properties and cooling cycles of HFC-134a, HFC-152a, and their mixtures
Andrey V Dobrokhotov, Evgeny E Ustjuzhanin, Boris F Reutov, Andrey G Testov, Natalya A Utenkova
HFC-134a, HFC-152a, and their mixtures are ozone-friendly substances. Experimental thermodynamic data of the hydrofluorocarbons (HFCs) were selected for a statistical treatment. Some equations of state (EOSs) were produced for the HFCs. A stable model of EOS for HFC-134a was determined by a many-step method. The EOS had the virial row form of the coefficient Z, where Z = p/ρRT, p is pressure, ρ is density, R is the gas constant, and T is temperature. The Carnahan – Starling – De Santis EOS was built for the blend HFC-134a/HFC-152a. Software programs were produced for some calculations of thermodynamic properties and characteristics of cooling cycles of the HFCs. The characteristics of cycles were compared with those of CFC-12. The results of the investigation showed that the blend HFC-134a/HFC-152a had some advantages relative to CFC-12 and HFC-134a. The blend can be used as an effective cooling liquid.