Jukes Timothy N, Choi Kwing-So
Faculty of Engineering, University of Nottingham, Nottingham, NG7 2RD, United Kingdom.
Phys Rev Lett. 2009 Jun 26;102(25):254501. doi: 10.1103/PhysRevLett.102.254501. Epub 2009 Jun 22.
A unique phenomenon in flow control is described, where the lift and drag on a circular cylinder could be modified for over eight vortex shedding cycles by a short pulse of dielectric-barrier-discharge plasma. This is equivalent to flow control for over 150 times the pulse duration, which seems to be due to a secondary vortex initiated by plasma that interacts with the von Kármán vortex formation and temporarily amplifies or suppresses the vortex street. Depending on the pulse timing, the drag and lift fluctuations could be increased by 22% and 50% or reduced by 8% and 40%, respectively, with a power saving ratio over 1000.
描述了一种流动控制中的独特现象，即通过介电势垒放电等离子体的短脉冲，圆柱上的升力和阻力可在超过八个涡街脱落周期内得到改变。这相当于在超过脉冲持续时间150倍的时间内进行流动控制，这似乎是由于等离子体引发的二次涡与冯·卡门涡形成相互作用，并暂时放大或抑制了涡街。根据脉冲定时，阻力和升力波动可分别增加22%和50%，或分别降低8%和40%，节能比超过1000。
