Flow field evolution and entrainment in a free surface plunging jet

  title={Flow field evolution and entrainment in a free surface plunging jet},
  author={Syed Harris Hassan and Tianqi Guo and Pavlos P. Vlachos},
  journal={Physical Review Fluids},
We investigate ambient fluid entrainment and near-field flow characteristics of a free surface plunging jet for five Reynolds numbers ranging from 3000 to 10000 using time-resolved stereo particle image velocimetry (SPIV). We present time-averaged velocities, RMS velocity fluctuations, mean entrainment and unsteady flow features and compare them with previous studies on free jets. We find that plunging jets have a smaller potential core length, and earlier decay of the mean centerline velocity… 

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