Particle Image Velocimetry
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Particle Image Velocimetry PIV is a non intrusive measurement technique used to obtain instantaneous velocity fields in a two dimensional region of gas or liquid flows. Spatial derivatives Light scattering particles are added to the flow. A laser beam The particle image is subdivided into small interrogation From the velocity field a range of spatial derivatives can be All three velocity components inside a two dimensional field A Tomographic PIV system with typically 2-4 cameras extends is formed into a light sheet illuminating seeding particles windows. For each interrogation window the average derived such as vorticity, shear stress and turbulent energy. of view can be measured using a second camera and stereoscopic the flow measurement into a full volume. Processing is done by twice with a short time interval Δ  The scattered light is t. particle image separation (Δx, Δy) is determined by cross- Capturing and computing a sequence of images can provide imaging. After image calibration the three components of the tomographic reconstruction of voxel intensities for each time recorded onto two consecutive frames of a high resolution correlation and localization of the correlation peak. When M information about the temporal behavior of the flow. velocity vector can be derived from the two displacement step followed by 3D3C-cross-correlation between interrogation digital camera. Microscopic, endoscopic and macroscopic is the magnification of the camera the velocity components projections. Scheimpflug lens arrangements keep all areas volumes. This allows for instantaneous measurement of all configurations cover a wide range of applications in gaseous (u,v) in this interrogation window is given by u=(1/M)(Δx/Δt) of the image plane in focus. three velocity components in a three dimensional measurement Downsview House / Grove Technology Park / Grove, Oxon, OX12 9FF / UK E-Mail: info@lavision.com / www.lavisionuk.com Tel. +44-(0)-870-997-6532 / Fax +44-(0)-870-762-6252 volume (3D3C) visualizing the 3D flow structure. LaVision GmbH Anna-Vandenhoeck-Ring 19 / D-37081 Goettingen / Germany E-Mail: sales@lavision.com / www.lavision.com Tel. +49-(0)551-9004-0 / Fax +49-(0)551-9004-100 211 W. Michigan Ave. / Suite 100 / Ypsilanti, MI 48197 / USA E-Mail: sales@lavisioninc.com / www.lavisioninc.com Phone: (734) 485-0913 / Fax: (240) 46