Generalised dissipative particle dynamics with energy conservation: density- and temperature dependent potentials.

0511363 - ÚCHP 2020 RIV GB eng J - Článek v odborném periodiku
Avalos, J.B. - Lísal, Martin - Larentzos, J.P. - Mackie, A.D. - Brennan, J.K.
Generalised dissipative particle dynamics with energy conservation: density- and temperature dependent potentials.
Physical Chemistry Chemical Physics. Roč. 21, č. 45 (2019), s. 24891-24911. ISSN 1463-9076. E-ISSN 1463-9084
Grant ostatní: MCIU(ES) CTQ2017-84998-P; ONR(US) 12-001
Institucionální podpora: RVO:67985858
Klíčová slova: heat * simulation * fluid
Obor OECD: Physical chemistry
Impakt faktor: 3.430, rok: 2019
Způsob publikování: Omezený přístup

We present a generalised, energy-conserving dissipative particle dynamics (DPDE) method appropriate for the non-isothermal simulation of particle interaction force fields that are both density- and temperaturedependent. A detailed derivation is formulated in a bottom-up manner by considering the thermodynamics of small systems with the appropriate consideration of the fluctuations. Connected to the local volume is a local density and corresponding local pressure, which is determined from an equation-of-state based force field that depends also on a particle temperature. Compared to the original DPDE method, the formulation of the generalised DPDE method requires a change in the independent variable from the particle internal
energy to the particle entropy. As part of the re-formulation, the terms dressed particle entropy and the corresponding dressed particle temperature are introduced, which depict the many-body contributions in the local volume. The generalised DPDE method has similarities to the energy form of the smoothed dissipative particle dynamics method, yet fundamental differences exist, which are described in the manuscript. The basic dynamic equations are presented along with practical considerations for implementing the generalised DPDE method, including a numerical integration scheme based on the Shardlow-like splitting algorithm. Demonstrations and validation tests are performed using analytical equation-of-states for the van der Waals and Lennard-Jones fluids. Particle probability distributions are analysed, where excellent agreement with theoretical estimates is demonstrated. As further validation of the generalised DPDE method, both equilibrium and non-equilibrium simulation scenarios are considered, including adiabatic flash heating response and vapour–liquid phase separation.
Trvalý link: http://hdl.handle.net/11104/0305539