2-COLOR DIGITAL PIV EMPLOYING A SINGLE CCD CAMERA

An extension of two color particle image velocimetry (PIV) is describe d where the color images are recorded onto a single high-resolution (3 060 x 2036 pixel) color CCD sensor. Unlike mono-color CCD sensors, thi s system not only eliminates the processing time and the subsequent di gitization time of film-based PIV but also resolves the directional am biguity of the velocity vector without using conventional image-shifti ng techniques. For comparing the spatial resolutions of film and CCD d ata, a calibration experiment is conducted by recording the speckle pa ttern onto 35 mm color film and using a CCD sensor under identical con ditions. This technique has been successfully implemented for simulate d turbine film-cooling flows in order to obtain a more detailed charac terization of the coolant-injection phenomenon and its interaction wit h freestream disturbances.