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Phase behavior of dipolar fluids from a modified statistical associating fluid theory for potentials of variable
1Department of Chemical Engineering, Vanderbilt University, Nashville, TN 37235, USA.
The Journal of Chemical Physics
|September 27, 2006
Summary
A new statistical associating fluid theory (SAFT-VR+D) models dipolar fluids by accounting for dipole interactions. The theory accurately predicts thermodynamic properties and phase behavior for various dipolar fluids.
Area of Science:
- Physical Chemistry
- Statistical Mechanics
- Thermodynamics
Background:
- Modeling dipolar fluids requires accounting for complex intermolecular interactions.
- Existing theories may not fully capture the influence of dipole moments on fluid structure and properties.
Purpose of the Study:
- To present a new statistical associating fluid theory (SAFT-VR+D) for modeling dipolar fluids.
- To explicitly incorporate dipolar interactions into the SAFT framework.
- To validate the SAFT-VR+D equation against simulation data.
Main Methods:
- Development of the SAFT-VR+D equation of state.
- Utilizing the generalized mean spherical approximation (GMSA) for a reference fluid.
- Performing isothermal-isobaric and Gibbs ensemble Monte Carlo simulations.
- Comparing theoretical predictions with simulation results for monomer and chain fluids.
Main Results:
- The SAFT-VR+D equation generally provides good predictions for the phase behavior of dipolar fluids.
- Accurate modeling of thermodynamic properties for dipolar monomer and chain fluids.
- Identified deviations for fluids with large dipole moments and specific dipole orientations.
Conclusions:
- The SAFT-VR+D equation is a valuable tool for predicting the behavior of dipolar fluids.
- The theory shows good agreement with simulation data, particularly for less complex systems.
- Refinements, such as using the linearized exponential approximation, can improve accuracy for challenging cases.
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