PIV Experiment on the Turbulent Stripe in Poiseuille Channel Flow at the Transitional Reynolds Number

The instantaneous velocity fields at the Reynolds number from Re-m = 1 200 to Re-m = 2 600, were measured by particle image velocimetry (PIV) to investigate the flow structure in transitional region directly and many details about flow field. The high velocity region and low velocity region, which indicate the stripe structure at transitional Reynolds number, can be found in these instantaneous velocity fields. And then, the turbulent stripe, which is shown in former numerical simulation [1], was extracted from the reconstructed flow field based on Taylor's hypothesis. The borderline between high velocity stripe and low velocity stripe was observed to be inclined against the streamwise direction.