Thermal Conductivity Of Ternary Mixtures Research Articles

Thermal Conductivity and Density of (NH4)2SO4 + H2O, NH4NO3 + H2O, and (NH4)2SO4 + NH4NO3 + H2O Solutions at T = (278.15 to 333.15) K

The thermal conductivity of ammonium sulfate + water, ammonium nitrate + water, and ammonium sulfate + ammonium nitrate + water is of great significance in the national defense industry and military engineering for manufacturing of various energetic chemicals. The measurements, covering a temperature range from (278.15 to 333.15) K, have been performed by a transient hot-wire technique over a wide range of concentrations. The densities of ternary aqueous solutions of ammonium sulfate + ammonium nitrate are also presented at the same temperature covering different portions of ammonium sulfate and ammonium nitrate. The thermal conductivities of binary aqueous solutions of ammonium salts are correlated by polynomial functions in terms of temperature and weight fraction for the purpose of interpolation. The Aseyev equation in terms of weight fraction is also used to represent the thermal conductivities of ternary mixtures of these compounds. The ideal mixing rule of Young has been successfully applied to correlate the ternary densities of aqueous ammonium sulfate + ammonium nitrate solutions based on relevant binary solution properties. The agreement between the correlation and the experimental data is pretty good.

Thermal conductivity of ternary mixtures for concrete pavements

Abstract This study used a standard procedure to measure the thermal conductivity of ternary concrete mixtures and investigated several factors influencing thermal conductivity. Three different coarse aggregates (Kentucky limestone, Mexican limestone, and river gravel) were used for the concrete mixtures. The measured thermal conductivity of concrete is significantly affected by the type and percentage of coarse aggregate, and moisture content. This finding was confirmed statistically by an Analysis of Variance (ANOVA) method. To understand the effect of supplementary cementitious materials (SCMs), the thermal conductivity of the control and ternary mixtures were measured and provided for use in Portland cement concrete (PCC) pavement design. The thermal conductivity of ternary mixtures increased by 7–10% due to an increase of 1% in moisture. The study developed a model equation that predicts the thermal conductivity of concrete as a function of moisture content and coarse aggregate percentage.

Heat capacities and thermal conductivity of ternary mixtures of water+ethanol+1,2-ethanediol between 75 and 350 K

The heat capacities of two concentrations of the ternary systems of 1,2-ethanediol, ethanol and water have been measured with an adiabatic calorimeter in the temperature range 80–350 K. These mixtures exhibited complex phase transitions in the solid state. A very broad heat capacity anomaly starting from 130 to 240 K was observed in the heat capacity curves and three transition peaks were found in this temperature range in addition to the melting peak. Experiments have demonstrated that the cooling rates had no obvious influence on the heat capacity anomaly. The thermal conductivity of the ternary systems were measured with an instantaneous heating wire conductometer in the temperature range from 233.15 to 343.15 K. All of the heat capacity and thermal conductivity results in temperature range between 221 and 350 K were correlated with temperature for practical applications.

ChemInform Abstract: TRANSPORT PROPERTIES OF MULTI‐COMPONENT POLAR GAS MIXTURES CONTAINING MONO‐, DI‐, AND TRIMETHYLAMINES

AbstractDie Viskositäts‐ und Wärmeleitfähigkeitskoeffizienten von Mono‐, Di‐ und Trimethylamin sowie ihrer binären Gemische bei 25‐250°C wurden gemessen.

Transport Properties of Multi-component Polar Gas Mixtures Containing Mono-, Di-, and Trimethylamines

Abstract The viscosity and thermal conductivity coefficients of monomethylamine (MMA), dimethylamine (DMA), and trimethylamine (TMA), and their binary mixtures have been measured in the temperature range 25–250 °C. In addition, determinations of thermal conductivity of ternary mixtures at 33 and 88 °C and of several quaternary mixtures (with ammonia) at 33 °C have been made. The results are discussed in the light of modern kinetic theory of gases. Finally, the coefficients of self-diffusion and mutual diffusion in binary mixtures of these gases are estimated from the experimental viscosity results.

Thermal conductivity of ternary gas mixtures

Thermal conductivities of ternary mixtures of N 2-Ne-H 2, O 2-N 2-Ne, and Kr-Ar-H 2 gas systems are measured at six temperature levels in the range 40–175°C. These data are used to evaluate the predictive procedures of the thermal conductivity of multicomponent gas mixtures as developed by several authors. This and a parallel study on quaternary mixtures provide a guidance to predicting conductivity values of multicomponent gas mixtures.

The thermal conductivity of mixtures of nitrogen, ammonia and hydrogen

The thermal conductivity of binary and ternary mixtures of nitrogen, ammonia and hydrogen has been measured at temperatures in the range 25 to 149°C. The apparatus used was of the hot wire type as modified by Callear & Robb, with accommodation effects almost eliminated by the use as thermometer not of the same wire as served as a source of heat but of a second wire. The accuracy of measurement was about 1% . For every binary mixture the dependence of thermal conductivity on composition (expressed in terms of mole fractions) was far from linear, and for mixtures of nitrogen and ammonia there was a composition for which the thermal conductivity was a maximum. A comparison with results obtained by earlier workers showed that the measurements of Gruss & Schmick for mixtures containing ammonia are reliable, as are those of Wassiljewa for mixtures of oxygen and hydrogen, but the results of Ibbs & Hirst for mixtures of nitrogen and hydrogen are to be rejected. The dependence of the thermal conductivity K on the mole fractions x i has been discussed in terms of the equation K = Ʃ i { K i /(1 + Ʃ j A ij x j / x i )} due to Wassiljewa. This equation, with A ij assumed independent of composition, represented the results for binary mixtures excellently. Within the limits of error attainable experimentally, there was no discernible dependence of A ij on temperature. An extrapolation of the present results to higher temperatures should therefore be fairly reliable; the thermal conductivities of the pure components are the only quantities which would have to be measured at the high temperatures concerned. A semi-empirical rule, due to Lindsay & Bromley, for predicting values of A ij , was found to give satisfactory results. The remarkably wide applicability of this rule to mixtures of polyatomic gases has been discussed. The results for N 2 + H 2 at the lowest temperature (25°C) have also been compared with the more rigorous theory of Hirschfelder. Wassiljewa’s equation, with values of A ij derived from the results for binary mixtures, gives almost as good an account of ternary mixtures, though there appear to be significant, if small, discrepancies. It follows that measurements on binary mixtures suffice to predict with reasonable accuracy the thermal conductivity of ternary mixtures. This, coupled with the approximate temperature independence of A ij , has important implications. For example, in combustion problems reliable estimates of thermal conductivities of mixtures at elevated temperatures are constantly needed.

Formulas for Thermal Conductivity of Ternary Gas Mixtures

The thermal conductivities of ternary mixtures of neon, argon, and krypton have been recently reported by the authors. In the present paper these values have been compared with those calculated from the two simple generalized expressions for the thermal conductivity of a ternary mixture, one of which is obtained from an extension of the Enskog's expression for the binary thermal conductivity while the other from the Lindsay-Bromley formula. It is found that the latter generalization yields values which are in better agreement with the experiment, provided the two constants of the Lindsay-Bromley formula are determined experimentally from binary conductivity.

Thermal Conductivity of Binary and Ternary Rare Gas Mixtures

The thermal conductivity of the binary gas mixtures Nc-A, Ne-Kr and A-Kr has been measured at 38°C for various concentrations by using the `thick wire' variant of the `hot wire' method. These data are likely to be of great use for gas analysis in the usual experiments on diffusion and thermal diffusion and have, therefore, been represented by semi-empirical equations giving the conductivity over the entire range of concentration. The experimental values of thermal conductivity have been compared with those calculated on the Lennard-Jones 12-6 model and the modified Buckingham exp-six model. A simple modification of the Lindsay-Bromley formula has been suggested and is found to reproduce the experimental data extremely well. The thermal conductivity of the ternary mixture Ne-A-Kr has also been measured for different compositions of the mixture.