Pairwise adaptive thermostats for improved accuracy and stability in dissipative particle dynamics

Journal Article · Tue Nov 01 04:00:00 EDT 2016 · Journal of Computational Physics

DOI:https://doi.org/10.1016/J.JCP.2016.07.034· OSTI ID:22622206

Leimkuhler, Benedict; Shang, Xiaocheng

We examine the formulation and numerical treatment of dissipative particle dynamics (DPD) and momentum-conserving molecular dynamics. We show that it is possible to improve both the accuracy and the stability of DPD by employing a pairwise adaptive Langevin thermostat that precisely matches the dynamical characteristics of DPD simulations (e.g., autocorrelation functions) while automatically correcting thermodynamic averages using a negative feedback loop. In the low friction regime, it is possible to replace DPD by a simpler momentum-conserving variant of the Nosé–Hoover–Langevin method based on thermostatting only pairwise interactions; we show that this method has an extra order of accuracy for an important class of observables (a superconvergence result), while also allowing larger timesteps than alternatives. All the methods mentioned in the article are easily implemented. Numerical experiments are performed in both equilibrium and nonequilibrium settings; using Lees–Edwards boundary conditions to induce shear flow.

• OSTI ID: 22622206
• Journal Information: Journal of Computational Physics, Journal Name: Journal of Computational Physics Vol. 324; ISSN JCTPAH; ISSN 0021-9991
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ACCURACY
BOUNDARY CONDITIONS
COMPUTERIZED SIMULATION
CONVERGENCE
CORRELATIONS
DIFFERENTIAL EQUATIONS
EQUILIBRIUM
FEEDBACK
FRICTION
INTERACTIONS
MOLECULAR DYNAMICS METHOD
STABILITY
STOCHASTIC PROCESSES
THERMODYNAMICS
THERMOSTATS