TITLE:
Jet Flapping Control with Acoustic Excitation
AUTHORS:
Shouichiro Iio, Ken Hirashita, Yusuke Katayama, Yoshiaki Haneda, Toshihiko Ikeda, Tomomi Uchiyama
KEYWORDS:
Jet Control; Rectangular Jet; Vortex; Hot Wire; Visualization
JOURNAL NAME:
Journal of Flow Control, Measurement & Visualization,
Vol.1 No.2,
July
15,
2013
ABSTRACT: The dynamics of flapping motion of a rectangular jet under acoustic excitation is studied experimentally by means of hot-wire measurement and flow visualization with smoke method. The excitation sufficiently enables“phase-lock”, which permitted us to extract the organized wave motion from a background field of finite turbulent fluctuations. The mean and fluctuation velocity are investigated and focused on the excitation frequency and the Reynolds number. As the excitation frequency decreases, it was found that the jet flapping and the jet spread were enhanced. The excitation with sub-harmonic frequency has significant effects on the rectangular jet behavior. The maximum value of the periodic velocity fluctuation strongly depends on the excitation frequency.