Abstract
Optical distortion due to inaccurate optical alignment, lens nonlinearity, and/or refraction by optical windows, fluid interfaces, and other optical elements of an experiment causes inaccuracy by introducing variable magnification. Since fractional changes in the magnification have a one-to-one effect on the accuracy of measuring the velocity, it is important to compensate for such distortions. A general experimental calibration procedure is described which determines the magnification matrix of a distorted imaging system, and an algorithm is presented to compute accurate velocity field displacements from measurements of distorted PIV images. These procedures form a basis for generalized stereoscopic PIV procedures which permit easy electronic registration of multiple cameras and accurate recombination of stereoscopic displacement fields to obtain the three-dimensional velocity vector field.
Original language | English (US) |
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Pages (from-to) | 1441-1454 |
Number of pages | 14 |
Journal | Measurement Science and Technology |
Volume | 8 |
Issue number | 12 |
DOIs | |
State | Published - Dec 1997 |
Externally published | Yes |
ASJC Scopus subject areas
- Instrumentation
- Engineering (miscellaneous)
- Applied Mathematics