Molecular theories of confined fluids

Journal Article · Wed Feb 15 04:00:00 EST 1989 · J. Chem. Phys.; (United States)

DOI:https://doi.org/10.1063/1.455985· OSTI ID:6563961

Vanderlick, T K; Scriven, L E; Davis, H T

Density profiles and normal pressures predicted by three different approximate density functional free energy theories and the Fischer--Methfessel approximation to the Yvon--Born--Green (YBG) equation are compared with computer simulation results for fluids confined between planar walls. All models require as input a homogeneous fluid equation of state. Comparisons are made using two mean-field equations of state, one based on a Clausius hard-sphere reference fluid and the other based on a Carnahan/Starling hard-sphere reference fluid. The simplest and oldest of the models, the generalized van der Waals model, becomes unphysical at high mean pore densities. The Carnahan/Starling version of Tarazona model agrees best overall with the simulations. This model represents a systematic improvement on the generalized van der Waals model and is computationally the most complicated of all models examined. The YBG and generalized hard-rod models are not as accurate as the Tarazona model, but they capture the qualitative trends observed in the simulations. Both of these models are intuitive extensions of the exact theory of one-dimensional hard rods, and are computationally much simpler than the Tarazona model.

• Research Organization: Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455
• OSTI ID: 6563961
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 90:4; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
COMPUTERIZED SIMULATION
CONFINEMENT
DENSITY
FLUIDS
LAYERS
LIQUIDS
MATHEMATICAL MODELS
PHYSICAL PROPERTIES
SIMULATION
STRUCTURE FACTORS
YVON METHOD