Simulation of interacting elastic sheets in shear flow: Insights into buckling, sliding, and reassembly of graphene nanosheets in sheared liquids

In liquid-based material processing, hydrodynamic forces are known to produce severe bending deformations of two-dimensional (2D) materials such as graphene. The non-linear rotational and deformation dynamics these atomically thin sheets is extremely sensitive particle-particle interactions. To investigate this problem, we developed a computational model the flow elastic suspended in linear shear flow, solving full fluid-solid coupling problem two-dimensional, slender-body, Stokes regime. Both single pairs close proximity analyzed. Despite being critical non-dimensional rate yielding single-particle buckling comparable order magnitude that reported for fully three-dimensional, disk-like sheets. For interacting sheets, interactions lead either parallel sliding or bending, depending on value an elasto-viscous number based particle length. sufficiently low rigidity large rates, initially stacked sheet reattachment after separation, unlike rigid case. A peeling-like where lubrication provides viscous bonding force observed when one two more than other. Practical implications graphene processing exfoliation discussed.