NTRS - NASA Technical Reports Server

Back to Results
A fiber-optic technique for the measurement of contact angle in a clearance-fit pin-loaded holeA fiber-optic technique for measuring contact angle during pin loading of a specimen is proposed. The experimental design and procedures for loading a 49.8-mm-diameter instrumented pin into an quasi-isotropic graphite-epoxy specimen are described. The optical fiber was located just above the surface of the pin outer diameter in order to obtain accurate pin-hole contact-angle measurements at increasing load levels. The movement of the optical fiber through the no-contact, contact, and no-contact regions is discussed; the photodiode output decreased monotonically as the fiber moved from the no-contact to the contact region and then decreased monotonically as the fiber moved from the contact region to the no-contact region. Variations in the contact angle measurements are examined as function of applied load level. The measurements are compared to contact angle values obtained using a finite element analysis and an electrical technique; it is determined that the data correlate well.
Document ID
Document Type
Reprint (Version printed in journal)
Prabhakaran, R.
(Old Dominion University Norfolk, VA, United States)
Naik, R. A.
(PRC Kentron, Inc. Hampton, VA, United States)
Date Acquired
August 13, 2013
Publication Date
April 1, 1987
Publication Information
Publication: Experimental Techniques
Volume: 11
ISSN: 0732-8818
Subject Category
Instrumentation And Photography
Funding Number(s)
Distribution Limits
No Preview Available