Effects of Reynolds Number on Flow-Mediated Interaction between Two Cylinders

This paper studies the interaction between two cylinders of an identical diameter immersed in quiescent fluid. The master cylinder carries out forced vibration, while the adjacent slave cylinder is elastically-mounted and has only one-degree-of-freedom along the centreline between the two cylinders. In this study, the geometry of the problem is fixed, with an initial gap ratio of the two cylinders of 0.9 and a non-dimensional vibration amplitude of the master cylinder of 0.477. In total, 7480 two-dimensional cases have been simulated to cover the parameter space of the problem, with the the Reynolds number ranging from 10 to 330, the structural damping factor of the slave cylinder ranging from 0 to 0.2, the mass ratio of the slave cylinder ranging from 1.5 to 2.5, and the master cylinders oscillation frequency ratio ranging from 0.05 to 3.2. Both the resonance amplitude and resonance frequency are found to increase with the Reynolds number. A critical Reynolds number is discovered, beyond which the vibration centre of the slave cylinder drifts away from the master cylinder, but below which the vibration centre of the slave cylinder approaches the master cylinder. This effect is amplified when the master cylinder vibrates at a higher frequency ratio.National Natural Science Foundation of China (51479111 and 51628901)， University of Edinburgh and EPSRC (EP/P020267/1)， ARCHER UK National Supercomputing Service， Cambridge Service for Data Driven Discover