Spatio-temporal spectral analysis of a forced cylinder wake
Abstract
The wake of a circular cylinder performing rotary oscillations is studied using hydrodynamic tunnel experiments at . Two-dimensional particle image velocimetry on the mid-plane perpendicular to the axis of cylinder is used to characterize the spatial development of the flow and its stability properties. The lock-in phenomenon that determines the boundaries between regions of the forcing parameter space were the wake is globally unstable or convectively unstable is scrutinized using the experimental data. A novel method based on the analysis of power density spectra of the flow allows us to give a detailed description of the forced wake, shedding light on the energy distribution in the different frequency components and in particular on a cascade-like mechanism evidenced for a high amplitude of the forcing oscillation. In addition, a calculation of the drag from the velocity field is performed, allowing us to relate the resulting force on the body to the wake properties.
Cite
@article{arxiv.1109.5825,
title = {Spatio-temporal spectral analysis of a forced cylinder wake},
author = {Juan D'Adamo and Ramiro Godoy-Diana and José Eduardo Wesfreid},
journal= {arXiv preprint arXiv:1109.5825},
year = {2011}
}
Comments
8 pages, 8 figures