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Inviscid Flow Field Effects: Experimental resultsThe aero-optical distortions due to invisid flow effects over airborne laser turrets is investigated. Optical path differences across laser turret apertures are estimated from two data sources. The first is a theoretical study of main flow effects for a spherical turret assembly for a Mach number (M) of 0.6. The second source is an actual wind tunnel density field measurement on a 0.3 scale laser turret/fairing assembly, with M = 0.75. A range of azimuthal angles from 0 to 90 deg was considered, while the elevation angle was always 0 deg (i.e., in the plane of the flow). The calculated optical path differences for these two markedly different geometries are of the same order. Scaling of results to sea level conditions and an aperture diameter of 50 cm indicated up to 0.0007 cm of phase variation across the aperture for certain forward look angles and a focal length of F = -11.1 km. These values are second order for a 10.6 micron system.
Document ID
19800017102
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Otten, L. J., III
(Air Force Weapons Lab. Kirtland AFB, NM, United States)
Gilbert, K. G.
(Air Force Weapons Lab. Kirtland AFB, NM, United States)
Date Acquired
August 10, 2013
Publication Date
April 1, 1980
Publication Information
Publication: NASA. Ames Res. Center Proc. of the Aero-Optics Symp. on Electromagnetic Wave Propagation Aircraft (SEE N80-25588 16-34)
Subject Category
Fluid Mechanics And Heat Transfer
Accession Number
80N25599
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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