TR PIV Experimental Investigation on Bypass Transition Induced by a Cylinder Wake

The process of laminar to turbulent transition induced by a cylinder wake was studied by TR PIV in a water channel. The generation of secondary transverse vortex structure and its evolution along the streamwise are tracked, also, a low‐speed hump is found in the near‐wall region along the bypass transition zone, which becomes more obvious further downstream. At the later stage, hairpin vortex can be seen, and its head is almost vertical to the wall.