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Abstract

Wet granular matter is a useful system for studing the dynamics which emerge in systems far from thermal equilibrium. It is easily accessible by experiments as well as simulations. With the help of time- as well as event-driven molecular dynamics simulations, wet granular matter was studied in this thesis. The energy injection which is necessary to drive the system out of thermal equilibrium was done by two highly different sinusoidal driving mechanisms. The first one was sinusoidal shaking whilst the second one was sinusoidal shearing. The interaction with the liquid in the system was modeled by the minimal capillary model and the thin-thread model, respectively. They account for the dissipation of energy such that the system can reach a steady state.In the first part of this thesis sinusoidal shaking was employed enabling the system to reside in states which are very reminiscent of solids, fluids or gases known from systems in thermal equilibrium. In the second part of this thesis, sinusoidal shearing was used to drive the wet granular matter. Phase diagrams were presented which showed a solid and a fluidized state which was followed by a study of the rich and complex dynamics emerging in the fluidized state in the sheared granular matter.In summary, extensive numerical simulations were performed on wet granular matter in this thesis. This was possible due to the remarkably simple model (the minimal capillary model) which is used to describe the capillary interaction. A derivation of this model (the thin thread model) allowed for a significant performance increase when simulating. An amazingly rich set of dynamical behavior was found for wet granular matter using different driving methods. In many cases very simple models, which only incorporate little of the actual complexity of the problem, were able to predict some of their features. In spite of their simplicity, in many cases a good qualitative agreement between simulations and experiment is found.