Spatiotemporal unsteady dynamics of wall-bounded jet induced by a wide-sector dielectric barrier discharge plasma actuator

Authors:
Publisher website
Google Scholar
Abstract
This study experimentally characterizes the unsteady induced-flow response of a wide-sector dielectric barrier discharge plasma actuator (WS-DBD-PA) designed to extend the flow-control capability of conventional geometric DBD actuators, which predominantly impart streamwise momentum. Planar two-dimensional particle image velocimetry is employed to characterize the evolution of the near-wall jet under unsteady actuation. Owing to the coupling between a streamwise near-wall jet and a wall-normal vortex response, the WS-DBD-PA produces a broad near-wall induced flow within the sector region. The transient evolution of this induced flow can be classified into four stages: vortex-core formation, vortex growth, jet expansion, and stabilized jet development. Vorticity–velocity correlation analysis indicates that duty cycle and pulse frequency jointly regulate near-wall momentum injection and downstream diffusion. Reduced-order analyses based on proper orthogonal decomposition and dynamic mode decomposition further show that the duty cycle mainly affects the energy envelope, whereas the pulse frequency modulates the discreteness of momentum input, together influencing the transition between jet- and vortex-dominated flow responses. Under the tested unsteady-actuation conditions, the nondimensionalized velocity profiles collapse onto a self-similar trend, which can be empirically described by a quadruple-Gaussian correlation with good agreement (R2 ≈ 0.95). Overall, the results provide experimental evidence, within the present planar measurement framework, for interpreting the coupled streamwise-jet and wall-normal vortex response of the WS-DBD-PA under unsteady actuation.
Funding Information
  • National Natural Science Foundation of China (52550007)
  • National Natural Science Foundation of China (52277167)
  • National Natural Science Foundation of China (61971345)
  • National Natural Science Foundation of China (202508610256)
  • Key Research and Development Projects of Shaanxi Province (2024ZDKY17)

This publication has 49 references indexed in Scilit: