Particle image velocimetry has been applied to the study of a canonical turbulent
boundary layer and to a turbulent boundary layer forced by transversal wall oscillations.
This work is part of the research programme at the Politecnico di Torino
aerodynamic laboratory with the objective of investigating the response of near-wall
turbulence to external perturbations. Results are presented for the optimum oscillation
period of 100 viscous time units and for an oscillation amplitude of 320 viscous
units. As expected, turbulent velocity fluctuations are considerably reduced by the
wall oscillations. Particle image velocimetry has allowed comparisons between the
canonical and forced flows in an attempt to find the physical mechanisms by which
the wall oscillation influences the near-wall organized motions.
Effective visualization of stereo particle image velocimetry vector fields of a turbulent boundary layer
