This work generalizes Evans' homogeneous nonequilibrium method for estimating heat transport coefficient to multispecies molecular systems described by general multibody potentials. The proposed method, in addition to being compatible with periodic boundary conditions, is shown to satisfy all the requirements of Evans' original method, namely, adiabatic incompressibility of phase space, equivalence of the dissipative and heat fluxes, and momentum preservation. The difference between the new equations of motion, suitable for mixtures and alloys, and those of Evans' original work are quantified by means of simulations for fluid Ar-Kr and solid GaN test systems.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1063/1.3459126 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Orientation and rotation of cholesteric liquid crystals relative to a heat flow studied by molecular dynamics simulation and implications for the Lehmann effect.
Phys Chem Chem Phys
January 2025
Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, 106 91 Stockholm, Sweden.
Alignment effects caused by a heat flow in the cholesteric liquid crystal phase of three coarse grained molecular model systems based on the Gay-Berne potential have been studied by molecular dynamics simulation. In order to keep the systems homogeneous, the Evans heat flow algorithm, where a fictitious mechanical heat field rather than a temperature gradient drives the heat flow, was used. It was found that the cholesteric axis orients in such a way that the heat flow and thereby the irreversible energy dissipation rate are minimized.
View Article and Find Full Text PDFPhase transition in a kinetic mean-field game model of inertial self-propelled agents.
Chaos
December 2024
California Institute of Technology, Pasadena, California 91125, USA.
The framework of mean-field games (MFGs) is used for modeling the collective dynamics of large populations of non-cooperative decision-making agents. We formulate and analyze a kinetic MFG model for an interacting system of non-cooperative motile agents with inertial dynamics and finite-range interactions, where each agent is minimizing a biologically inspired cost function. By analyzing the associated coupled forward-backward in a time system of nonlinear Fokker-Planck and Hamilton-Jacobi-Bellman equations, we obtain conditions for closed-loop linear stability of the spatially homogeneous MFG equilibrium that corresponds to an ordered state with non-zero mean speed.
View Article and Find Full Text PDFNon-Equilibrium Quantum Brain Dynamics: Water Coupled with Phonons and Photons.
Entropy (Basel)
November 2024
Dipartimento di Ingegneria Meccanica e Aerospaziale, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Turin, Italy.
We investigate Quantum Electrodynamics (QED) of water coupled with sound and light, namely Quantum Brain Dynamics (QBD) of water, phonons and photons. We provide phonon degrees of freedom as additional quanta in the framework of QBD in this paper. We begin with the Lagrangian density QED with non-relativistic charged bosons, photons and phonons, and derive time-evolution equations of coherent fields and Kadanoff-Baym (KB) equations for incoherent particles.
View Article and Find Full Text PDFSubgrid-scale model for large eddy simulations of incompressible turbulent flows within the lattice Boltzmann framework.
Phys Rev E
October 2024
School of Marine Science and Technology, Northwestern Polytechnical University, Xi'an, Shaanxi 710072, People's Republic of China.
Large eddy simulations are a popular method for turbulent simulations because of their accuracy and efficiency. In this paper, a coupling algorithm is proposed that combines nonequilibrium moments (NM) and the volumetric strain-stretching (VSS) model within the framework of the lattice Boltzmann method (LBM). This algorithm establishes a relation between the NM and the eddy viscosity by using a special calculation form of the VSS model and Chapman-Enskog analysis.
View Article and Find Full Text PDFInfluence of kinetic air-water interfacial partitioning on unsaturated transport of PFAS in sandy soils.
Sci Total Environ
December 2024
Civil & Environmental Engineering Department, Hydrologic Science and Engineering Program, Hydrologic Science & Engineering Program, ReNuWit-The Urban Water Engineering Research Center, Colorado School of Mines, Golden, CO 80401, USA. Electronic address:
Article Synopsis
- - This study explores how kinetic air-water partitioning influences the movement of PFAS (perfluoroalkyl substances) in sandy soil, particularly under dynamic unsaturated flow situations.
- - Short-chain PFAS act like conservative tracers with minimal partitioning, whereas longer-chain PFAS show non-equilibrium behavior, and the presence of air-water interfaces significantly affects their transport.
- - The research highlights that considering kinetic partitioning processes can more than double the mass flux of PFOS to groundwater, indicating a major impact on PFAS concentrations in porewater.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!