References

Accurate values for the cross second virial coefficients and dilute gas shear viscosities, thermal conductivities, and binary diffusion coefficients of the (CH 4 + C 3 H 8 ) and (CO 2 + C 3 H 8 ) systems were determined at temperatures from (150 to 1200) K using state-of-the-art computational approaches. The cross second virial coefficients were calculated semiclassically using the Mayer-sampling Monte Carlo method, while the transport properties were computed by means of the classical trajectory approach in conjunction with the kinetic theory of molecular gases. The required intermolecular potential energy surfaces (PESs) for the CH 4 −C 3 H 8 and CO 2 −C 3 H 8 interactions are reported in this work, whereas those for the CH 4 −CH 4 , CO 2 −CO 2 , and C 3 H 8 −C 3 H 8 interactions were taken from our previous work on the pure gases. All PESs are based on high-level quantum-chemical ab initio calculations and were fine-tuned to the best experimental data for the second virial and cross second virial coefficients. Overall, the agreement of the calculated thermophysical property values with the few available experimental data is satisfactory.

Section: Resultsmentioning

confidence: 79%

Section: Resultsmentioning

confidence: 99%

Cross Second Virial Coefficients and Dilute Gas Transport Properties of the (CH₄+ C₃H₈) and (CO₂+ C₃H₈) Systems from Accurate Intermolecular Potential Energy Surfaces

Hellmann

2017

“…Deviations of experimental data, an experimentally based correlation, and calculated values for the cross second virial coefficient of the CO 2 –C 2 H 6 molecule pair from the semiclassically calculated values of this work as a function of temperature: ●, Katayama et al; ○, Holste et al; ■, Jaeschke; □, Jaeschke et al; ◇, McElroy et al; ◆, Weber; △, Hou et al; ▲, Yang et al; solid line, correlation by Dymond et al; dashed line, semiclassical result for the unadjusted CO 2 –C 2 H 6 PES; dash-dot line, classical result for the adjusted CO 2 –C 2 H 6 PES; dotted lines, B 12 QFH ± U ( B 12 QFH ) with k = 2.…”

Section: Resultsmentioning

confidence: 80%

“…The calculated values for the cross second virial coefficient of the CO 2 –C 2 H 6 molecule pair are compared with most of the existing experimental data − and with the experimentally based correlation of Dymond et al in Figure . The error bars shown in this and all following figures always correspond to those given by the respective authors.…”

Section: Resultsmentioning

confidence: 91%

Cross Second Virial Coefficients and Dilute Gas Transport Properties of the Systems (CO₂+ C₂H₆) and (H₂S + C₂H₆) from Accurate Intermolecular Potential Energy Surfaces

Hellmann

2019

The cross second virial coefficients and dilute gas shear viscosities, thermal conductivities, and binary diffusion coefficients of the systems (CO2 + C2H6) and (H2S + C2H6) were determined with high accuracy at temperatures from (150 to 1200) K by means of statistical thermodynamics and the kinetic theory of polyatomic gases. The required intermolecular potential energy surfaces (PESs) for the CO2–C2H6 and H2S–C2H6 interactions are presented here, while the like-species interactions were modeled employing PESs developed previously as part of our studies on the pure gases. All PESs are based on high-level quantum-chemical ab initio computations and are represented analytically by site–site potential functions. The agreement between the calculated values for the investigated mixture properties and the few reliable experimental data is very satisfactory.

“…Second virial coefficients for pure gases are experimentally measured 2 or can be reliably estimated using corresponding-states correlations. , However, considerably less information is available for the cross virial coefficients, representing interactions between unlike, i.e. , i ≠ j , compounds, for instance, between Ar and Kr, between H 2 O and CO 2 , and so forth . Although it can be argued − that the theory of the second virial coefficients is one of the most rigorous theories of intermolecular interactions, accurate experimental data are still necessary, at least to check the intermolecular potential energy functions proposed.…”

Section: Introductionmentioning

confidence: 99%

Second Cross Virial Coefficients for Interactions Involving Water. Critical Data Compilation

Plyasunov

Shock

2003

Values of the second cross virial coefficients, B 12, and isothermal Joule−Thomson coefficients, φ12, for interactions involving water are compiled and, as necessary, evaluated from existing experimental data including PVT properties of gas mixtures, measurements of the pressure dependence of the molar excess enthalpies of a gas mixture, and measurements of the solubility of the condensed phases of H2O (liquid water or ice) in compressed gases. In all, there are data for interactions between water and 32 other compounds, and among these, nine interactions involve compounds with appreciable dipole moments. These B 12 values, typically available over a limited temperature range, are extrapolated to high temperatures by means of the Tsonopoulos corresponding-states correlation. Finally, the temperature dependence of the second cross virial coefficients between water and solutes at temperatures up to 1200 K is approximated by an empirical polynomial equation, the coefficients of which are tabulated for each interaction.