  A novel supersonic jet oscillating method is investigated both experimentally
and numerically. A rectangular primary supersonic jet is issued into a confined
chamber with sudden enlargement. Secondary control jets are issued from the
top, and bottom backwards-facing step regions formed due to sudden enlargement.
The secondary jet also expands in the confined chamber shrouding the primary
jet from the top and bottom sides. The primary jet is oscillated in the
transverse direction by blowing the secondary jets in the streamwise direction
in a pulsating manner with a phase shift. The out-of-phase secondary jet
blowing causes the primary jet to periodically adhere to the upper and lower
part of the confined chamber, causing flapping of the primary jet and acting as
a supersonic fluidic oscillator. The supersonic jet oscillation characteristics
are experimentally investigated using shadowgraph type flow visualization
technique and steady and unsteady pressure measurements. Quantitative analysis
of the shadowgraph images using the construction of $y-t$ and $y-f$ plots
reveals the presence of periodic jet oscillation with a discrete dominant
frequency similar to the secondary jet excitation frequency. The existence of
linearity between the excitation frequency and the flapping jet frequency on
the low-frequency ($0.66-6.6$ Hz) side is first proven experimentally. Later,
the high-frequency ($16.67-5000$ Hz) operation extent of the supersonic fluidic
oscillator is further demonstrated using unsteady computational studies owing
to the existing experimental facility's limitations. It is found from the
computational studies that there exists a limiting oscillation frequency for
the present fluidic oscillator (nearly $4.486$ kHz with the particular
geometric size and the injection momentum considered in the present study).
