Abstract
In response to the phasing out of CFCs in refrigeration applications, tetrafluoroethane (R134a) refrigerant and polyol ester lubricants have been developed to replace the traditional R12/mineral oil systems. This article describes a statistical thermodynamic method that has been used to model the thermodynamic behaviour of R134a and an ISO 15 polyol ester (i.e. a polyol ester having a viscosity of 15cSt at 40C). The molecular interaction and the excess chemical potential of the mixtures is calculated by simulating the vapour pressure of the mixture and comparing it with some available experimental data. The phase diagram of the mixture is successfully simulated using a modified equation-of state thermodynamic model. The result of the theoretical simulation is compared with experimental findings. Excellent agreement is obtained. Other quantities such as change in free energy, enthalpy, entropy and volume change on mixing are calculated for the temperature range –40° C to + 100° C.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
