Enhanced KR-Fundamental Measure Functional for Inhomogeneous Binary and Ternary Hard Sphere Mixtures

• Published in: Communications in theoretical physics Vol. 55; no. 1; pp. 46 - 58
• Main Author: Zhou, Shi-Qi (世琦 周)
• Format: Journal Article
• Language: English
• Published: IOP Publishing 01.01.2011
• Subjects: Approximation; Computational fluid dynamics; Computer simulation; Density; Fluid flow; Fluids; Particle theory; Walls; 不均匀; 密度分布; 混合物; 状态方程; 硬球流体
• ISSN: 0253-6102
• DOI: 10.1088/0253-6102/55/1/10

An enhanced KR-fundamental measure functional （FMF） is elaborated and employed to investigate binary and ternary hard sphere fluids near a planar hard wall or confined within two planar hard walls separated by certain interval. The present enhanced KR-FMF incorporates respectively, for aim of comparison, a recent 3rd-order expansion equation of state （EOS） and a Boublfk＇s extension of Kolafa＇s EOS for HS mixtures. It is indicated that the two versions of the EOS lead to, in the framework of the enhanced KR-FMF, similar density profiles, but the 3rd-order EOS is more consistent with an exact scaled particle theory （SPT） relation than the BK EOS. Extensive comparison between the enhanced KR-FMF-3rd-order EOS predictions and corresponding density profiles produced in different periods indicates the excellent performance of the present enhanced KR-FMF-3rd-order EOS in comparison with other available density functional approximations （DFAs）. There are two anomalous situations from whose density profiles all DFAs studied deviate significantly; however, subsequent new computer simulation results for state conditions similar to the two anomalous situations are in very excellent agreement with the present enhanced KR-FMF-3rd-order EOS. The present paper indicates that （i） the validity of the ＂naive＂ substitution elaborated in the present paper and peculiar to the original KR-FMF is still in operation even if inhomogeneoas mixtures are being dealt with; （ii） the high accuracy and self-consistency of the third order EOS seem to allow for application of the KR-FMF-third order EOS to more severe state conditions; and （iii） the ＂naive＂ substitution enables very easy the combination of the original KR-FMF with future＇s more accurate but potentially more complicated EOS of hard sphere mixtures.