Dynamic Viscosity for HFC-134a + Polyether Mixtures up to 373.15 K and 140 MPa at Low Polyether Concentration. Measurements and Modeling
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- 作者：Marí ; a J. P. Comuñ ; as ; Antoine Baylaucq ; Christian Boned ; and Josefa Ferná ; ndez
- 刊名：Industrial & Engineering Chemistry Research
- 出版年：2004
- 出版时间：February 4, 2004
- 年：2004
- 卷：43
- 期：3
- 页码：804 - 814
- 全文大小：224K
- 年卷期：v.43,no.3(February 4, 2004)
- ISSN：1520-5045
文摘
This paper reports viscosity data for mixtures containing a refrigerant (HFC-134a) and alubricant (triethylene glycol dimethyether, TriEGDME, or tetraethylene glycol dimethyl ether,TEGDME), at 12% of TriEGDME or 14% mass fraction of TEGDME. The measurements (140data points) were obtained at various pressures (between 10 and 140 MPa) in the monophasicliquid state from 293.15 to 373.15 K. Because HFC-134a and the polyethers are not in the samesingle phase at normal pressure and temperature (the refrigerant is a gas, whereas the polyethersare liquids), accurate measurements of their mixtures require specific procedures for preparationof the samples and filling of the apparatus. A specially designed isobaric-transfer falling-bodyviscometer is used in this work. The viscosities of the mixtures are, on average, 40% higherthan that of the pure refrigerant, and this increase is more noticeable at low temperatures. Theexperimental viscosities have been used to check the predictive and correlation ability of severalviscosity models (mixing rules, Geller and Davis method, self-referencing model, hard-spheretheory, free-volume model, and friction theory). Most of the studied models underestimate thedynamic viscosity values over all of the temperature and pressure ranges investigated.