Instantaneous measurement of unsteady three-dimensional velocity fields with photogrammetric PIV

Knowledge about the three-dimensional structure of a velocity field is important for understanding multiple flow phenomena associated with off design operation of pumps and turbines, acoustic emissions or two phase flow to name but a few. The measurement of three-dimensional unsteady velocity fields in industrial applications requires a robust, easy to use and universal measurement system. Existing 3D-3C-Particle-Image Velocimetry (PIV) Systems like Holographic PIV (HPIV) or Defocus-PIV suffer from restrictions to the optical accessibility of the volume to be investigated and a sophisticated optical set up. Hence the objective of this paper is to present the advanced Photogrammetric PIV (PPIV), a robust and easy to use 3D-3C-PIV system applicable to flows in areas with limited optical accessibility like in housings of rotary machines.