An investigation of a planar, shear-driven 3-D turbulent boundary layer (3DTBL) was performend to examine the effects of variable spanwise shear on rtubulence structure and flow physics of the non-equilibrium flow field. Particle image velcimetry (PIV) measurements were acquired in both the xy-plane (perpendicular to the wall) and the xz-plane (parallel to the wall) to examine modifications to the near-wall turbulence when subject to varying strengths of crossflow. The overall effect of the crossflow in this shear driven 3DTBI is to disrupt near-wall coherent structures, resulting in a shift to smaller length scales. This leads to increased transport and a thickening of the inner region of the boundary layer as indicated by a notable deceleration of the streamwise velocity. The crossflow is also associated with increases in the (normal and shear) Reynolds stresses, particularly over the translating wall section, as well as a shift in peak values away from the wall region. The most highly sheared case also experimences an increase in the turbulent kinetic energy due to enhanced production.
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