Flow Characteristics of Non Circular Synthetic Jets

Abstract

Our study aimed to investigate the flow characteristics of circular and non-circular orifice configurations: a slot, a square, and an equilateral triangle, and to compare the results in order to investigate which orifice configuration is a better solution of synthetic jet for thermal control management. The synthetic jet actuators were tested at their resonance frequency where 500 PIV images were acquired randomly for each orifice configuration and were averaged to give the time-averaged flow fields. Velocity profiles along the axial and traverse directions where generated and analyzed. The results showed highly coherent structures for the circular and square configuration, and high spreading rate and mixing for the slot configuration which makes it most preferable configuration. Nomenclature Do Orifice diameter De Effective (hydraulic) diameter Ū Mean velocity in the streamwise direction V Mean velocity in the transverse direction Uo Mean velocity at the orifice exit in the streamwise direction UCL Centerline mean velocity u rms velocity in the streamwise direction x Streamwise distance from the orifice r Radial distance from the centerline