In this paper a video digital-imaging technique is described that is currently being developed to permit the assessment of surface temperature and shear stress distributions using liquid crystals. The background to liquid crystal research in aerodynamics is given first and this is followed by a description of the experimental apparatus, along with the method of digital analysis of the color components of the liquid crystal traces. Some typical calibrations of the crystals are then presented as well as details of the main aspects that need to be considered when using liquid crystals as a quantitative measurement technique. The use of the technique is then illustrated by taking the simple case of a heated circular jet impinging normally onto a flat plate.

Date Published: 1 October 1991
PDF: 12 pages
Proc. SPIE 1489, Structures Sensing and Control, (1 October 1991); doi: 10.1117/12.46593

Published in SPIE Proceedings Vol. 1489:
Structures Sensing and Control
John Breakwell; Vijay K. Varadan, Editor(s)