Correlating Thermal-Conductivity Data for Ternary Liquid Mixtures

Abstract

The performance of several semi-empirical expressions for correlating the temperature, pressure and composition dependence of the thermal conductivity (λ) of pure organic liquids and mixtures was investigated. The temperature and pressure dependence is adequately represented by Chisholm approximants of order (1, 1) or (2, 1) with five and eight adjustable constants, respectively. The fully predictive Vredeveld equation uses mass fractions as the composition variable. It significantly underestimated λ values for the R32 + R125 + R134a ternary refrigerant system. Binary predictive models with one or two adjustable parameters include the quadratic Scheffé polynomial and its corresponding Padé approximant, the cubic "Margules" model and the theoretical Wassiljewa equation. It was found that the Padé (2, 2) approximant and the Wassiljewa equation satisfactorily correlated the extensive ternary mixture data published by Rowley and coworkers. Best results were obtained when the mole fraction was used as a composition variable. The predictive capability of the models was checked using the R32 + R125 + R134a ternary refrigerant system. Combining rules were used for cross parameters such that the temperature and pressure dependence was incorporated via the pure fluid properties. Model parameters were fixed using binary data alone. In this case, the quadratic Scheffé, Padé (2, 2), and Wassiljewa (with temperature-and pressure-independent parameters) all provided satisfactory predictions for ternary mixtures.

Sn/Mn/Bi2O3 Ternary Pyrotechnic Time Delay Compositions

“…Padè mixture models are families of rational polynomials based on Scheffe K-polynomials . They are eminently suitable for correlating complex mixture property behavior. − Consequently, the data was correlated using the Padè mixture model shown in eq where u is the burning rate in mm·s –1 and the w i values are the mass fractions of the different components corresponding to the ternary system Bi 2 O 3 (1)–Mn (2)–Sn (3). The a ijk and b ij values are adjustable model constants.…”

Measurement of the Thermal Conductivity of 1-Butyl-3-methylimidazolium l-Tryptophan + Water + Ethanol Mixtures at T = (283.15 to 333.15) K

“…The thermal conductivities of water and ethanol at different temperatures have been studied by many researchers and can be correlated as a function of temperature using a second-order polynomial 34,41…”

“…The thermal conductivities of water and ethanol at different temperatures have been studied by many researchers and can be correlated as a function of temperature using a second-order polynomial , where λ i (W·m –1 ·K –1 ) is the thermal conductivity of pure component i , T (K) is the temperature, and subscript i represents each pure component as 1 for [BMIM]­[ l -trp], 2 for water, and 3 for ethanol. a 0 , a 1 , and a 2 are the correlation coefficients.…”

“…In this work, the thermal conductivities of [BMIM]­[ l -trp], water, ethanol, and their binary and ternary mixtures from 283.15 to 333.15 K over the whole scale of concentration have been determined at room pressure, and the experimental data were correlated by the second-order Scheffé polynomial. − …”

Prediction of thermal conductivity of liquid and vapor refrigerants for pure and their binary, ternary mixtures using artificial neural network

“…An empirical approach based on a limited number of fixed physical parameters [15] was considered; a new equation to describe the thermal conductivity of R-32, R-125, R134a, and R-143a for practical use, applicable over a wide range of temperature and pressure has also been proposed [16]. Semi-empirical approaches for correlating thermal conductivity data for multicomponent liquid mixtures [17,18] were studied, a method to estimate the thermal conductivity and the viscosity similar to cubic equations of state of halogenated hydrocarbon of pure substances in vapor and liquid regions [19,20] was proposed; thermal conductivity modeling of refrigerant mixtures in a three-parameter corresponding states format [21] was carried out. There are an extensive studies have been published in the literature on the thermal conductivity of mixed refrigerants [22,23,24] which suggested a correlation to calculate the thermal conductivity and viscosity of some alternative refrigerant mixtures such as R-507, R-404A, R-407C, and R-410A.…”