Author(s): D. Nehari; F. Ballio; V. Armenio; L. Adjlout
Linked Author(s): Francesco Ballio
Keywords: Oscillating flow; Three-dimensional analysis; Array of circular cylinders
Abstract: The three-dimensional oscillating laminar flow field around an array of circular cylinders is investigated for different values of the gap between the cylinders. Results for the 2D and 3D vortex patterns are well comparable with literature experiments. The space-time evolution of the vortex structures as well as of the forces on the cylinder are quantified. For the values of the Keulegan-Karpenter number and of the Reynolds number considered, vortex shedding appears to be asymmetric, thus inducing non-zero values of the transversal component of the force. The flow field is three-dimensional and significant modulations of the transversal force along the axis of the cylinder are present; conversely, the correspondent modulation of the in-line force is weak. The magnitude of both the in-line and transversal oscillations decrease for decreasing gap values. For very small values of the gap, however, the flow field becomes two-dimensional and symmetrical, and any transversal effects disappear.
Year: 2003