The paper contains new, representative equations for the viscosity and thermal conductivity of carbon dioxide. The equations are based in part upon a body of experimental data that have been critically assessed for internal consistency and for agreement with theory whenever possible. In the case of the low-density thermal conductivity at high temperatures, all available data are shown to be inconsistent with theoretical expectation and have therefore been abandoned in favor of a theoretical prediction. Similarly, the liquid-phase thermal conductivity has been predicted owing to the small extent and poor quality of the experimental information. In the same phase the inconsistencies between the various literature reports of viscosity measurements cannot be resolved and new measurements are necessary. In the critical region the experimentally observed enhancements of both trans: port properties are well represented by theoretically based equations containing just one adjustable parameter. The complete correlations cover the temperature range 200 K~T < 1500 K for viscosity and 200 K~T~l000 K for thermal conductivity, ~nd pressures up to 100 MPa. The uncertainties associated with the correlation vary according to the thermodynamic state from ± 0.3% for the viscosity of the dilute gas near room temperature to ± 5% for the thermal conductivity in the liquid phase. Tables of the viscosity and thermal conductivity generated by the representative equations are provided to assist with the confirmation of computer implementations of the calculation procedure.

The International Association for the Properties of Water and Steam (IAPWS) encouraged an extensive research effort to update the IAPS Formulation 1985 for the Viscosity of Ordinary Water Substance, leading to the adoption of a Release on the IAPWS Formulation 2008 for the Viscosity of Ordinary Water Substance. This manuscript describes the development and evaluation of the 2008 formulation, which provides a correlating equation for the viscosity of water for fluid states up to 1173K and 1000MPa with uncertainties from less than 1% to 7% depending on the state point.

We review the available experimental information on the thermodynamic properties of supercooled water and demonstrate the possibility of modeling these thermodynamic properties on a theoretical basis. We show that by assuming the existence of a liquid-liquid critical point in supercooled water, the theory of critical phenomena can give an accurate account of the experimental thermodynamic-property data up to a pressure of 150 MPa. In addition, we show that a phenomenological extension of the theoretical model can account for all currently available experimental data in the supercooled region, up to 400 MPa. The stability limit of the liquid state and possible coupling between crystallization and liquid-liquid separation are also discussed. It is concluded that critical-point thermodynamics describes the available thermodynamic data for supercooled water within experimental accuracy, thus establishing a benchmark for further developments in this area.

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A temperature gradient in a liquid mixture causes a concentration gradient through the Soret effect. We have developed an instrument to measure the Soret effect by observing the bending of a laser beam propagating horizontally through the liquid mixture subjected to a temperature gradient in the vertical direction. Our design of the liquid cell, with a long path length and controlled temperature uniformity, enables us to measure Soret coefficients with an accuracy of 1–3 %, higher than that obtained by previous investigators. In addition, by measuring the dynamic response of the beam deflection after imposition of the temperature gradient, we can also determine the mutual diffusion coefficient. We have applied the technique to mixtures of toluene and n-hexane over the temperature range 5–45 °C and to mixtures of ethanol and water at 25 °C. We have verified that the measured value of the Soret coefficient is independent of the magnitude of the temperature gradient imposed up to 14 K/cm. The Soret coefficients obtained for mixtures of toluene and n-hexane differ from the values obtained by previous investigators with a thermogravitational column method, but they are in good agreement with the results recently obtained by Köhler and Müller with a forced Rayleigh scattering method. For mixtures of ethanol and water, our Soret coefficients agree with the results obtained earlier by Kolodner et al., also with an optical beam-bending technique.