Session: 01-07-02 Industrial Fluid Mechanics

Paper Number: 65783

Start Time: August 12th, 10:50 AM

65783 - Time Resolved PIV Measurements of a Slot Lobed Jet Issuing Into a Crossflow 

The near field turbulent mixing of a round jet with three slot lobes issuing into a crossflow are investigated at a velocity ratio of 0.5. The interaction of the lobes and center round jet primarily occur just upstream and in the immediate exit of the jet, whose convective mixing is further complicated by the dominant freestream. Time-resolved particle image velocimetry measurements provide instantaneous velocity fields in the near exit region in both the  and  planes. Without the crossflow, the round and slot portions of the jet are found to exhibit a near perfect radial distribution of mass flow rate. Instantaneous and time-averaged velocity profiles reveal the effect of the slot lobes on the various shear layers and cumulative wake development. Reynold stress magnitudes indicate the turbulence generated by the central round jet, outer slots, and crossflow, revealing their competing effects towards homogeneity. Frequency domain analysis in the  plane reveals that low-frequency harmonics in the wake of the jet provided greater energy contributions than the higher-frequency harmonics along the leading edge shear layer. This behavior is most readily attributed to the low velocity ratio condition. The  and  plane measurements provide valuable insight into the three separate fundamental flow streams and their momentum exchanges. These results are intended to serve analogous simulations, which should further investigate the extended trajectory of the jet downstream and/or its upstream chamber mixing.

Presenting Author: Michael Lewandowski Texas A&M University

Authors:

Michael Lewandowski Texas A&M University
Paul Kristo Texas A&M University
Abdullah Weiss Texas A&M University
Mark Kimber Texas A&M University