Changes between Version 244 and Version 245 of WikiStart

Timestamp:

Oct 19, 2016, 6:18:07 PM (8 years ago)

Author:

peakall3je

Comment:

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WikiStart

@@ -120 +120 @@
 
 '''Particle Imaging Velocimetry (PIV)'''
-A Spectra-Physics xxxx laser in conjunction with 3 cameras was used to provide PIV images. The laser light sheet was brought in parallel to the floor of the channel. The light sheet can then be racked in the vertical through a series of steps through the use of a motorized traverse and a mirror; the laser is pointed down at the mirror producing the light sheet. The laser light sheet positions are then synchronized with the PIV cameras. The field of view extends from close to the upstream end of the first bend, towards the mid-point of the second bend.
+A Spectra-Physics xxxx laser in conjunction with 3 cameras was used to provide PIV images. The laser light sheet was brought in parallel to the floor of the channel. The light sheet can then be racked in the vertical through a series of steps through the use of a motorized traverse (tilted at 3.5 degrees to match the slope of the channel) and a mirror; the laser is pointed down at the mirror producing the light sheet. The laser light sheet positions are then synchronized with the PIV cameras. The field of view extends from close to the upstream end of the first bend, towards the mid-point of the second bend. Later experiments used larger seeding particles, 200 micron polystyrene particles for the flow seeding. These work very well for these situations where the measurement area is larger than 2 square metres. The PIV cameras consist of one Dalsa camera and two PCO cameras. These use xxx objective lenses.
 
 == 3.2 Definition of time origin and instrument synchronisation ==