Flow control over a circular cylinder using virtual moving surface boundary-layer control

Zhang, Xin; Choi, Kwing-So; Huang, Yong; Li, Hua-Xing

Abstract

Flow control study of a circular cylinder is carried out using symmetric dielectric barrier discharge (DBD) plasma actuators at the Reynolds number of 10,000. Here, two symmetric DBD plasma actuators are located at the top and bottom of the circular cylinder respectively, each of which induces pairs of counter-rotating starting vortices on both sides of exposed electrodes. The downstream starting vortices soon take the form of a wall jet along the freestream direction. On the other hand, the upstream starting vortices which interact with the incoming flow remain for some time, bringing in high momentum from the freestream to near-wall region, enabling the boundary layer to withstand the adverse pressure gradient and suppressing the separation around the circular cylinder. The rotating vortical structures around the circular cylinder created by the plasma actuators lead to a reduction in the drag coefficient of up to 25%, providing a similar effect to moving surface boundary layer control (MSBLC). This configuration of symmetric DBD plasma actuator, which is studied for the first time in this investigation, is therefore called virtual MSBLC. Our results also indicated that the control effect of virtual MSBLC can be enhanced with an increase in the momentum coefficient of plasma jet. Unlike traditional MSBLC devices, the virtual MSBLC based on symmetric DBD plasma actuator does not have profile drag and are without complicated mechanical systems.

Citation

Zhang, X., Choi, K., Huang, Y., & Li, H. (2019). Flow control over a circular cylinder using virtual moving surface boundary-layer control. Experiments in Fluids, 60(6), https://doi.org/10.1007/s00348-019-2745-y

• Journal Article Type: Article
• Acceptance Date: May 10, 2019
• Online Publication Date: May 31, 2019
• Publication Date: Jun 1, 2019
• Deposit Date: May 17, 2019
• Publicly Available Date: May 17, 2019
• Journal: Experiments in Fluids
• Print ISSN: 0723-4864
• Electronic ISSN: 1432-1114
• Publisher: Springer Verlag
• Peer Reviewed: Peer Reviewed
• Volume: 60
• Issue: 6
• Article Number: 104
• DOI: https://doi.org/10.1007/s00348-019-2745-y
• Keywords: Plasma actuator; Flow control; Dielectric Barrier Discharge; Moving surface boundary layer control
• Public URL: https://nottingham-repository.worktribe.com/output/2061564
• Publisher URL: https://link.springer.com/article/10.1007/s00348-019-2745-y
• Additional Information: Received: 15 January 2019; Revised: 8 May 2019; Accepted: 10 May 2019; First Online: 31 May 2019