Thermophysical Properties of Pure Refrigerants and Refrigerant Mixtures by Dynamic Light Scattering (DLS)
نویسندگان
چکیده
The present paper summarizes the activities at LTT-Erlangen on the field of thermophysical properties research for pure refrigerants and refrigerant mixtures. For the characterization of their thermophysical properties dynamic light scattering (DLS) has been intensively applied as a key tool during the past two decades. Beside a representation of the essential features of DLS for the determination of thermophysical properties, the present paper gives a complete compilation of all experimental data obtained until now at LTT-Erlangen for thermal diffusivity, speed of sound, kinematic viscosity, and surface tension of pure refrigerants and refrigerant mixtures under saturation conditions. For refrigerant mixtures of technical interest the paper includes a review of literature data and deals with a simple prediction method based on the properties of the pure components expressed as functions of the reduced temperature. This calculation scheme was found to be applicable for the prediction of both equilibrium properties and transport properties of multicomponent refrigerant mixtures with sufficient high accuracy.
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