一列に並んだ複数円形噴流中の渦挙動

抄録

Velocity fields of circular jets issued from circular orifices arrayed at an equal interval in a line, were studied with a central focus on the relation between the velocity and vortex motions. The interval of the circular orifices, which was the distance between jet exit centers, was 1.5 times greater than the diameter of the jet exit, and Reynolds number of the jets was 2500. In order to reveal the vortex motions and explore means of flow control, the jets were excited by a loudspeaker placed near the jet exit. Velocity was measured by a single normal hot wire probe, and mean velocity and turbulence intensity of the circular jets were examined. From the experimental results, the effect of the excitation appeared on the three-dimensional deformation and interaction of vortex rings, and the excitation frequency related to the instability of the shear layer near the jet exit was effective for increasing the jet cross-sectional area.