Stereo-PIV measurements have been performed to investigate the wake behind a vibrissa (facial hair) from a seal. Previous experiments have proven the capability of seals to detect the wake swimming fish by using only their vibrissae as a sensory system. Also it can be observed that the vibrissae of seals exhibit a unique 3D shaped structure. The aim of the present investigation is, to learn the fluid mechanic aspects of the wake detection and to understand the influence of the 3D surface structure on the detection capabilities. The measurements have made extensive use of a Stereo-PIV device,which allows the capturing of the full un-steady 3D vector field on a set of 2D planes with microscopic length scales. 丹迪粒子圖像測(cè)速儀 Dantec PIV