An 8 mm diameter air bubble oscillating at 30 Hz produces a concentrated streaming jet with extraordinary characters.
An 8 mm air bubble oscillating at 20 Hz produces a low speed vortex.
The compliant surface induced synthetic jet exhibits Kelvin-Helmholtz instability in the shear-zone
Flow pathlines in the wake behind a bluff-body triangle wedge exhibits strong divergent motions near the free surface (Fr=0.5)
Dynamic interactions of two air bubbles (D= 8 mm , f=50 Hz) separated by a 2 mm gap generates (a) high-speed merged synthetic jet with small static curvature (b) low-speed vortex with large static curvature, and (c) two almost parallel jets when actuated out-of-phase.
Flow pathlines in the turbulent free-surface wake in the shear-layer zone. The interactions of usteady free-surface with shedding vortices induce strong downward drafts toward the sub-surface regions. It is hypothesiszed that this phenomenon could have contributed to the cascade of entrained air-bubbles.
An array of 8 mm air bubbles (D=8 mm, f=60 Hz) oscillating in-phase in a fully devleoped turbulent boundary layer (Retheta=1000) dynamically modulate the vortical structures near the wall surface.
Large-magnitude dynamic curvature change in the compliant surface (induced by pulsive loading) generates a traveling vortex ring.
Coupled oscillation of two neighbouring air-water interface (D= 8 mm, f=50 Hz) induces a fountain type oscillation.