The free flow field of a multi-slotted array of Synthetic Jets (SJ) has been experimentally investigated in quiescent ambient at Reynolds and Strouhal numbers, Re = 128 and St = 0.11, respectively. The multi-slotted SJ actuator is composed of twelve rectangular slots with an aspect ratio of 15 (for a width of ~1 mm) and off-centered with respect to the cavity center. Experiments were conducted at three equally-spaced cross sectional planes inspecting two consecutive slots by means of phase-locked Stereo-Particle Image Velocimetry. At the slot exit, the statistical analysis reveals that the SJ exhibits an asymmetric spreading with respect to the geometrical axis of the slot, being tilted of about ~14.8° on the side where the cavity extends. This asymmetric pattern determines a small recirculation region slightly downstream of the slot exit. On the other hand, the flow field appears two-dimensional at the mid spanwise distance between the two slots. The phase-locked flow fields exhibit counter-rotating vortical patterns that convect downstream from the slot exit during the ejection phase. These vortices develop in longitudinal direction at 3.4 slot widths and then dissipate as they travel further downstream.
Phase-resolved measurements on a multi-slotted Synthetic Jets actuator / Ceglia, Giuseppe; Invigorito, Marco; Chiatto, Matteo; Greco, CARLO SALVATORE; Cardone, Gennaro; DE LUCA, Luigi. - (2019), pp. 1-1. (Intervento presentato al convegno 13th International Symposium on Particle Image Velocimetry tenutosi a Munich nel July 22-24, 2019).
Phase-resolved measurements on a multi-slotted Synthetic Jets actuator
Matteo Chiatto;Carlo Salvatore Greco;Gennaro Cardone;Luigi de Luca
2019
Abstract
The free flow field of a multi-slotted array of Synthetic Jets (SJ) has been experimentally investigated in quiescent ambient at Reynolds and Strouhal numbers, Re = 128 and St = 0.11, respectively. The multi-slotted SJ actuator is composed of twelve rectangular slots with an aspect ratio of 15 (for a width of ~1 mm) and off-centered with respect to the cavity center. Experiments were conducted at three equally-spaced cross sectional planes inspecting two consecutive slots by means of phase-locked Stereo-Particle Image Velocimetry. At the slot exit, the statistical analysis reveals that the SJ exhibits an asymmetric spreading with respect to the geometrical axis of the slot, being tilted of about ~14.8° on the side where the cavity extends. This asymmetric pattern determines a small recirculation region slightly downstream of the slot exit. On the other hand, the flow field appears two-dimensional at the mid spanwise distance between the two slots. The phase-locked flow fields exhibit counter-rotating vortical patterns that convect downstream from the slot exit during the ejection phase. These vortices develop in longitudinal direction at 3.4 slot widths and then dissipate as they travel further downstream.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
