Three-Dimensional, Transonic Rotor Flow Field Reconstructed from Holographic Interferogram Data.

reportActive / Technical Report | Accession Number: ADA160902 | Open PDF

Abstract:

Holographic interferometry and computer-assisted tomography CAT are used to determine the transonic flow field of a model rotor blade in hover. A pulsed ruby laser recorded 40 interferograms with a 61 cm-diam view field near the model rotor-blade tip operating at a tipo Mach number of 0.90. After digitizing the interferograms and extracting fringe-order functions, the data are transferred to a CAT code. The CAT code then calculates pressure coefficients in several planes above the blade surface. The values from the holography-CAT method compare favorably with previously obtained numerical computations and laser velocimeter measurements at most locations near the blade tip. The results demonstrate the techniquess potential for three-dimensional transonic rotor flow studies. Keywords Holographic interferometry Computer assisted tomography Helicopter aerodynamics Transonic aerodynamics.

Author(s):
Kittleson, J. K. ; Yu, Y. H. ; Becker, F.
Author Organization(s):
NATIONAL AERONUATICS AND SPACE ADMINISTRATION MOFFETT FIELD CA AMES RESEARCH CENTER
Descriptive Note:
Technical memo.,
Pagination:
0021

Security Markings

DOCUMENT & CONTEXTUAL SUMMARY

Distribution:
Approved For Public Release

RECORD

Collection: TR
Identifying Numbers
Report Number(s):
NASA-A85347, NASA-TM-86816
Monitor Series:
TM-86816, TR-85-A-10
 Subject Terms
Joint Capability Areas:
JCA_5_Command and Control; JCA_5.3_Planning; JCA_5.5_Direct; JCA_5.5.1_Communicate Intent and Guidance; JCA_1.2.7_Experimentation
Modernization Areas:
Directed Energy
Communities of Interest:
Air Platforms
Descriptor(s):
*HELICOPTER ROTORS, *FLOW VISUALIZATION, *INTERFEROGRAMS, *HOLOGRAPHY, *TOMOGRAPHY, *TRANSONIC FLOW, MEASUREMENT, COMPUTATIONS, MODELS, NUMERICAL ANALYSIS, PULSED LASERS, ROTOR BLADES(ROTARY WINGS), BLADES, SURFACES, INTERFEROMETRY, HELICOPTERS, COEFFICIENTS, PRESSURE, COMPUTER APPLICATIONS, HOVERING, AERODYNAMICS, LASER VELOCIMETERS, RUBY LASERS
Field(s)/Group(s):
Holography, Fluid Mechanics
Report Date:
1985 Oct 01