Flow past an oscillating circular cylinder in a channel with an upstream splitter plate

A transversely oscillating circular cylinder confined in a channel has the potential to promote mixing and heat transfer at moderate Reynolds number flows. In the present study, simulation results for flow past a circular cylinder subjected to forced cross-flow oscillations in a straight channel with an upstream splitter plate are presented in a wide range of cylinder oscillation frequencies, including the subharmonic, superharmonic, and primary lock-in regimes. Simulations are performed at Re=100, with cylinder oscillation amplitude of 0.4 diameters and a blockage ratio of 1/3. A spectral element algorithm based on the arbitrary Lagrangian Eulerian formulation is utilized. The numerical method exhibits spectral accuracy and allows large mesh deformation in the computational domain without mesh refinements. The main objective of this study is systematic investigations of the cylinder oscillation on the vortex shedding mechanism, downstream vortex patterns, and forces exerted on the cylinder.