Elucidating the near-critical fluid behavior and properties of multicomponent mixtures using molecular dynamics simulations
Abstract
This proposal is for a molecular dynamics centric approach to characterizing near critical and critical point properties of mixtures of fluids. Drawing upon recent progress in the molecular dynamic understanding and characterization of near critical properties in pure components, we extend the approach to systems with an additional degree of freedom i.e. global mixture composition. Molecular dynamics can be used to understand mechanistic details of molecular behavior in the near equilibrium region, explore spatiotemporal-compositional heterogeneities, and assign the loci of critical points, vapor liquid equilibria, correlation length, and other properties including sound speed, thermal conductivity, etc. for mixtures. In this work, we focus on multicomponent mixtures of a representative undecane-propyl-benzene-nitrogen system and propose to extend one of our molecular level definitions of the critical point (based on scale invariant fluctuations) to a thermodynamic pseudo-state. We anticipate that such definitions and molecular understanding will be useful for analyzing multicomponent systems with fluctuations in composition, beyond those of density (clustering). Recognizing the need for experimental data to anchor the intermolecular forces in mixtures, we further propose complementary experimental measurements of vapor liquid equilibria of selected compositions. Finally, we propose X-ray scattering measurements as an opportunity to complement and associate molecular level information including correlation lengths and fluctuation time and length-scales.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Mar 14, 2024
- Source ID
- FA95502310751
Entities
People
- Kenneth Brezinsky
Organizations
- Air Force Office of Scientific Research
- United States Air Force
- University of Illinois Urbana–Champaign