Abstract
The current study explored the mean and turbulent flowfield features of a confined transverse slot jet. The slot jet spans 95% of the full channel spanwise dimension, a geometrical feature found to result in a highly three-dimensional mean flowfield. The transverse slot jet produces a recirculation bubble that has similarities to that found for the flow downstream of a rearward-facing step. The flowfield results were compared with a 2:1 expansion ratio step flow and the observations were discussed in the context of how the transverse slot jet may provide advantages compared with a sudden expansion for subsonic combustors. High turbulence levels are achieved and large turbulent length scales are produced for strong transverse slot jets. The momentum ratio of the jet to that of the channel is found to be a governing parameter, and the dimensions of the recirculation zone scale with this parameter. A series of models constructed in ANSYS/CFX-10 were done to complement the experimental work and showed that the three-dimensionality of the mean flow disappears when the slot jet extends fully across the channel.