Abstract
The effect of periodic disturbances introduced with oscillating plates has been investigated on a jet issuing from a rectangular nozzle. The oscillating plate consists of a laminated piezoelectric element and stainless plate. The experiment was performed at the outlet velocity of U_0=5(m/s). The cross sectional area of the rectangular nozzle has a size of 10mm×10mm. Velocity components were measured with single hot-wire probe and CTA. Oscillating frequency was set at 1/4, 1/3, 1/2 and 1 times of a natural occurrence frequency. From the streamwise variation of turbulent intensity on the jet centerline, disturbance was classified into three non-dimensional oscillating frequency of 0, 1/2 and 1/3. In an early stage of the jet, stable large-scale vortical structures were observed at the non-dimensional oscillating frequency of 1/2 and 1/3. The decay of the streamwise mean velocity on the centerline and growth rate of the half width increase at the non-dimensional oscillating frequency of 1/2.
