The interaction of a plane shear layer with a thin flat plate located on the centerline of a shear layer has been investigated experimentally. The shear layer velocity ratio is 0·375, and its Reynolds number is ΔU θ0 v = 625. It is found that disturbances from the vicinity of the disturbing plate leading edge feed back into the initial disturbance field of the shear layer to alter significantly its amplitude, increasing it at certain frequencies and suppressing it at other frequencies by negative feedback. An analytical model is developed for the linear stability region of the shear layer in which the system is treated as a closed-loop, frequency-dependent amplifier with wavelength selection according to a phase condition.
ASJC Scopus subject areas
- Mechanical Engineering