Thermophysical Properties of a Quaternary Refrigerant Mixture: Comparison of Dynamic Light Scattering Measurements with a Simple Prediction Method
- 124 Downloads
Dynamic light scattering (DLS) has been used for the measurement of several thermophysical properties of a quaternary refrigerant mixture R-125/143a/32/134a in its liquid phase under saturation conditions. The thermal diffusivity and sound speed have been obtained by light scattering from bulk fluids over a temperature range from about 293 K up to the liquid–vapor critical point. By applying the method of DLS to a liquid–vapor interface, also called surface light scattering (SLS), the saturated liquid kinematic viscosity and surface tension can be determined simultaneously. These properties have been measured from about 243 to 343 K. The results are discussed in comparison with literature data and with a simple prediction method based on the mass-weighted properties of the pure components, expressed as functions of the reduced temperature. Once again, the simple prediction method was shown to be applicable for the calculation of different transport and other thermophysical properties of multicomponent refrigerant mixtures and this with sufficiently high accuracy for technical practice. Moreover, the input data for the simple prediction scheme can be reduced without loss of accuracy by treating binary or ternary mixtures as a subset of the multicomponent mixture.
KeywordsDynamic light scattering Kinematic viscosity Prediction Quaternary mixture Refrigerants Sound speed Surface tension Thermal diffusivity
Unable to display preview. Download preview PDF.
- Berne B.J., Pecora R., Dynamic Light Scattering (Robert E. Krieger, Malabar, 1990)Google Scholar
- Chu B. (1991). Laser Light Scattering. Academic Press, New YorkGoogle Scholar
- Langevin D. (1992) Light Scattering by Liquid Surfaces and Complementary Techniques. Marcel Dekker, New YorkGoogle Scholar
- Leipertz A., A.P. Fröba, in Diffusion in Condensed Matter – Methods, Materials, Models, ed. by Heitjans P., J. Kärger (Springer, Berlin, 2005), pp. 579–618Google Scholar
- Kraft K., Bestimmung von Schallgeschwindigkeit und Schalldämpfung transparenter Fluide mittels der Dynamischen Lichtstreuung. Dr.-Ing. thesis, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen (1995)Google Scholar
- A.P. Fröba, Simultane Bestimmung von Viskosität und Oberflächenspannung transparenter Fluide mittels Oberflächenlichtstreuung. Dr.-Ing. thesis, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen (2002)Google Scholar
- Yata J., Hori M., Minamiyama T., in Proc. 11th Jap. Symp. (Thermophys. Props., Tokyo, 1990), pp. 111–114Google Scholar
- Kraft K., Leipertz A., in Proc. Int. Conf. CFCs (The Day After, Padova, 1994), pp. 435–442Google Scholar
- Lemmon E.W., McLinden M.O., Huber M.L., NIST Standard Reference Database 23: Reference Fluid Thermodynamic and Transport Properties – REFPROP, Version 7.0. (National Institute of Standards and Technology, Standard Reference Data Program, Gaithersburg, Maryland, 2002)Google Scholar
- Weber L.A., Defibaugh D.R. (1996). J. Chem. Eng. Data 41, 1447–1480Google Scholar
- Lemmon E.W., Private Communication (National Institute of Standards and Technology, Boulder, Colorado, 2006)Google Scholar