Please use this identifier to cite or link to this item:
Title: Simulation of flow around a row of square cylinders
Authors: KUMAR, SR
Keywords: 2 Circular-Cylinders
Lattice Boltzmann Method
Low Reynolds-Numbers
Coupled Wakes
Flopping Regime
Issue Date: 2008
Citation: JOURNAL OF FLUID MECHANICS, 606(), 369-397
Abstract: In this paper, the low-Reynolds number (Re = 80) flow around a row of nine square cylinders placed normal to the oncoming flow is investigated using the lattice-Boltzmann method. The effects of the cylinder spacing on the flow are studied for spacing to diameter ratios of 0.3 to 12. No significant interaction between the wakes is observed with spacings greater than six times the diameter. At smaller spacings, the flow regimes as revealed by vorticity field and drag coefficient signal are: synchronized, quasi-periodic and chaotic. These regimes are shown to result from the interaction between primary (vortex shedding) and secondary (cylinder interaction) frequencies; the strength of the latter frequency in turn depends on the cylinder spacing. The secondary frequency is also related to transition between narrow and wide wakes behind a cylinder. The mean drag coefficient and Strouhal number are found to increase rapidly with a decrease in spacing; correlations of these parameters with spacing are proposed. The Strouhal number based on gap velocity becomes approximately constant for a large range of spacings, highlighting the significance of gap velocity for this class of flows. It is also possible to analyse the vortex pattern in the synchronized and quasi-periodic regimes with the help of vorticity dynamics. These results, most of which have been obtained for the first time, are of fundamental significance.
ISSN: 0022-1120
Appears in Collections:Article

Files in This Item:
There are no files associated with this item.

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.