Molecular dynamics simulation study on nanoscale flow interference between two circular cylinders

The nanoscale phenomenon of two identical circular cylinders arranged in a side-by-side configuration in steady cross-flow was investigated using molecular dynamics simulations with the Lennard-Jones potential model at a low Reynolds number (Re=22). L*/D*, the centre-to-centre pitch ratio, ranged from 1.0 to 2.0. Three basic flow patterns were observed and the results indicate that the characteristic ranges of the microscopic flow patterns are different from those of the macroscopic phenomenon. Single bluff-body vortex shedding range is L*/D*<1.1. Biased flow with synchronized vortex shedding range is 1.1<L*/D*<1.8 with the emergence of the typical biased flow at L*/D*=1.2 because of the presence of gap flow. Symmetric flow with synchronized vortex shedding range is L*/D*gt;1.8. All the boundaries of the L*/D* ranges corresponding to the three types of flow patterns in nanoscale are smaller than those in macroscopic phenomenon, which indicates significant scale effect.