Periodic flow between low aspect ratio parallel jets

The behavior of symmetric parallel jets was investigated experimentally. Two-component hot-wire surveys of the velocity field were performed over a jet region extending from the nozzle plate to a distance seven times the spacing between the nozzles. The objective of this study was to investigate an observed periodic behavior in the near-field region between parallel jets that increases infrequency as the nozzle widths decrease. This behavior was found to occur in parallel jets where nozzle widths are greater than 0.5 times the jet spacer width. The phenomena are attributed to bluff, body shedding in the near field and a confining effect of the outer shear layers.