Dynamic molecular dynamics ensembles for multiscale simulation coupling

Abstract

Molecular dynamics (MD) simulation has become a valuable tool in process engineering. Despite our efforts in software developments for large-scale molecular simulations over several years, which have amongst others enabled record-breaking trillion-atom runs, MD simulations are—as stand-alone simulations—limited to rather small time and length scales. To make bigger scales accessible, we propose to work towards a coupling of CFD solvers with our efficient MD software ls 1 mardyn. As a first step, we discuss extensions to our coupling software MaMiCo, addressing the challenge of efficiently sampling hydrodynamic quantities from MD: due to the high level of thermal fluctuations, MD ensemble considerations are required for sampling. We propose an extension of MaMiCo that allows to handle dynamic ensembles, i.e. to launch and remove MD simulations on-the-fly over the course of a coupled simulation. We explain the underlying implementation and provide first scalability results.