Visualization of the space-time impulse response of the subcritical wake of a cylinder

Publication Type:

Journal Article

Source:

PHYSICAL REVIEW E, AMERICAN PHYSICAL SOC, Volume 62, Number 3, Part B, ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA, p.4424-4426 (2000)

Keywords:

ABSOLUTE; BODIES; GLOBAL MODES; INSTABILITY; LOW REYNOLDS-NUMBERS; SELECTION; SPATIALLY DEVELOPING FLOWS; STABILITY

Abstract:

The well-known Benard-von Karman cylinder wake is one of the most challenging phenomena of fluid mechanics. As the Reynolds number of the flow around a cylinder passes through a critical value, alternating vortex shedding appears via a Hopf bifurcation. Theoretical studies of the wake have described the appearance of this self-sustained oscillation as the result of a convective to absolute transition resulting in the formation of a global mode. We illustrate here the convective global regime of the subcritical wake by analyzing visualizations of its impulse response.