This numerical study investigates a circular cylinder placed in a uniform stream and moving along a slender figure-8 path. A 2D computational method based on the finite difference method was used. Two aspects were investigated separately: the effect of in-line amplitude of oscillation and the effect of the frequency ratio. Computations for varying amplitude values were carried out at Re = 150, 200 and 250. Time-mean and rms values of force coefficients yielded smooth curves and tended to increase with amplitude. When plotted against frequency ratio in the domain of 0.69 to 0.98 at Re = 250, a jump was found in the time-mean values of lift and torque. This was also present in the energy transfer curves, and positive and negative values were found. Limit cycle curves from before and after a jump were symmetric, mirror images, and quite complex. Vorticity contours also showed a mirror image pre- and post-jump. These results indicate the possibility of symmetry-breaking bifurcation.

This content is only available via PDF.
You do not currently have access to this content.