The research in my group focuses on algorithms as well as applications for large scale molecular dynamics (MD) simulations.
Recently the emphasis of the applications in my group is shifting to the
investigation of molecular aspects of flow and assembly of bio-molecules. In
flow there are both fundamental aspects that are not well understood,
especially at surfaces, as well as questions about particular applications
where molecular aspects become more important due to the smaller scales in
micro- and nanofluidics. Although even in nanofluidics most of the system is
still best described by continuum (or meso-) dynamics, details of molecular
interactions can play an essential role. An important case is the the
three-phase contact line in wetting. Molecular processes that can not be
desrcibed in terms of continuum physics play a crucial role here. Molecular
dynamics simulations are the only way to study these effects in detail. We
will study the processes at the contact line under non-equilibrium conditions:
one case if flow over structured substrates, another is boiling heat
transfer. A second project, which has recently started, looks at assembly of
bio-molecules triggered byu changes in pH. The first application is to spider
silk, which is of high interest as a biomaterial. A second application is to
cellulose fibrils with the end goal of producing stronger materials. The
assembly of bio-molecules is often controlled by changes in pH an ion
concentrations, which affect protonation states. These states can not be
measured experimentally and the only way to get access to these is molecular
simulation (with a dynamic protonation method). Ordering of molecules is
either steered directly by the interactions given by nature in the case
of spider silk or can be influenced through flow in the case of nanocellulose,
which will be studied at the meso scale using rod models. The effective forces between the fibrils will be parametrized using molecular dynamics simulations which can take into account the nature of surface groups and the ionic composition of the solution.
All this work in done using the open-source GROMACS molecular simulation package and all algorithmic improvements will be made directly available to the community.