Massively parallel molecular-continuum simulations with the macro-micro-coupling tool

Efficient implementations of hybrid molecular-continuum flow solvers are required to allow for fast and massively parallel simulations of large complex systems. Several coupling strategies have been proposed over the last years for 2D/ 3D, time-dependent/ steady-state or compressible/incompressible scenarios. Despite their different application areas, most of these schemes comprise the same or similar building blocks. Still, to the authors’ knowledge, no common implementation of these building blocks is available yet. In this contribution, the Macro-Micro-Coupling tool is presented which is meant to support developers in coupling mesh-based methods with molecular dynamics. It is written in C++ and supports two- and three-dimensional scenarios. Its design is reviewed, and aspects for massively parallel coupled scenarios are addressed. Afterwards, scaling results are presented for a hybrid simulation which couples a molecular dynamics code to the Lattice Boltzmann application of the Peano framework.