Vapor-liquid equilibria of a low GWP refrigerant, R-1234ze(E), mixed with a POE lubricant

Novel vapor-liquid-equilibria data (P-T-x) and liquid densities of binary mixtures of an emerging low-GWP (Global Warming Potential) refrigerant, R-1234ze(E), and a polyol ester (POE) oil, RL68H, are measured. Data are presented for oil mass fractions ranging from 0 to 0.85 over a temperature range from -10 to 60°C, and the results are compared to the properties of mixtures of R-134a with RL68H. In addition to providing new pure-refrigerant and refrigerant/oil property data, a comparison of the performance of five mixture models is undertaken, namely: the Wilson model, NRTL, UNIQUAC, Heil, and Raoult’s law. Overall, the Heil model provides the best agreement in pressure predictions for R-1234ze(E)/RL68H mixtures, with RMS deviations less than 0.5%, while NRTL RMS deviations are less than 1%. However, comparable performance was found for the much simpler Raoult’s law, with increased deviations at the highest oil concentration. Model sensitivity and applicability of Raoult’s law for refrigerant/oil mixtures in general are investigated. The experimental data and modeling results presented are especially valuable for engineers working in the automotive air-conditioning and refrigeration industries. The refrigerant R-1234ze(E) is one of the leading alternatives for replacing R-134a and is a member of the HFO family of chemicals that includes other low-GWP refrigerants. Accurate models for the new refrigerants and refrigerant/oil mixtures are essential for designing and analyzing refrigeration and air-conditioning systems with reduced environmental impact.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Mechanical Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Bock, Jessica J.

Contributors dc:contributor

• Jacobi, Anthony M.
• Brewster, M. Quinn
• Hrnjak, Predrag S.
• Wang, Xinlei

• R-1234ZE
• vapor-liquid equilibria (VLE)

Statement dc:rights

• Copyright 2015 Jessica Bock

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/88188

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/88188