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Method for Laminar Boundary Layer Transition Visualization in FlightDisclosed is a method of visualizing laminar to turbulent boundary layer transition, shock location, and laminar separation bubbles around a test surface. A liquid crystal coating is formulated using an unencapsulated liquid crystal operable in a temperature bandwidth compatible with the temperature environment around the test surface. The liquid crystal coating is applied to the test surface, which is preferably pretreated by painting with a flat, black paint to achieve a deep matte coating, after which the surface is subjected to a liquid or gas flow. Color change in the liquid crystal coating is produced in response to differences in relative shear stress within the boundary layer around the test surface. The novelty of this invention resides in the use of liquid crystals which are sensitive to shear stress to show aerodynamic phenomena such as a boundary layer transition, shock location, and laminar separation bubbles around a test surface.
Document ID
19890003180
Acquisition Source
Langley Research Center
Document Type
Other - Patent
External Source(s)
LAR-13554-1
Authors
Bruce J Holmes
(Langley Research Center Hampton, United States)
Peter D Gall
(Langley Research Center Hampton, United States)
Date Acquired
August 14, 2013
Publication Date
October 4, 1988
Publication Information
Publisher: United States Patent and Trademark Office
Subject Category
Aerodynamics
Accession Number
89N12551
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
Patent
US-PATENT-4,774,835
Patent Application
US-PATENT-APPL-SN-929862
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