Jets in Crossflow - Simultaneous PIV/PLIF measurements

摘要

Simultaneous planar laser-induced fluorescence (PLIF) and panicle image velocimetry (PIV) yield measurements of two-dimensional jet fluid concentration and velocity fields in turbulent crossflowing jets. The jet-to-crossflow velocity ratio is r - 5.7 and the jet exit Reynolds number is roughly 5000. Two flow configurations are studied, one in which the jet nozzle is flush with the tunnel wall and the other where the nozzle protrudes into the uniform region of the tunnel flow. The averaged scalar and velocity fields show a strong similarity in growth rates and centerline decay rates between the two configurations when using the centerline coordinate s. A possible approach to wake scaling is seen in the velocity fields, but is not evident in the scalar fields. Results are presented for the scalar flux components and the turbulent shear stress, as examples of the fluctuation quantities accessible by the present data.