Turbulence and Shear Flow Phenomena -1 First International Symposium

ISBN Print: 1-56700-135-1

JET CONTROL BY COUNTERFLOW

要約

The expansion of axisymmetric jets and their initial turbulence level are considerably enhanced by using a suction collar of sufficient length around the nozzle and by producing a counterflow near the jet exit. Visualizations and velocity-fluctuations spectra show that the near-field of the jet is the seat of low-frequency large-size ejections. The observed phenomena seem to be due to a large positive pressure gradient and to recirculation generated by the suction in the collar chamber.