Application of PIV for investigation of the flow details in boundary layers with respect to two particular topics is considered. The study was performed in German Aerospace Center, G.o.ttingen, Germany. The first problem is the determination of the localskin friction coefficient of the turbulent boundary layer. It was shown that PIV measurements of the linear part of the mean-velocity profile in the viscous sublayer can be used. The second point is reliability of PIV in experiments on laminar-turbulent transition in shear layers. Normally, the method provides a sufficient resolution of rather strong velocity variations. In the present study we are interested in potential application of PIV for investigating much weaker laminar-flow disturbances found at the early stage of transition to turbulence.
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