Theoretical Investigations of Boundary Layer Stability

Item

Title
Theoretical Investigations of Boundary Layer Stability
Date
1966
Index Abstract
Coming Soon
Photo Quality
Not Needed
Report Number
AFFDL TR 64-184
Creator
Raetz, Gibbs S.
Brown, W. Byron
Corporate Author
Northrop Corporation
Laboratory
Air Force Flight Dynamics Laboratory
Extent
142
NTRL Accession Number
AD809388
Identifier
AD0809388
Access Rights
Export Control
Distribution Classification
1
Contract
AF 33(657)-11618
DoD Project
1366
DoD Task
136612
DTIC Record Exists
No
Distribution Change Authority Correspondence
AFFDL LTR
Abstract
The mathematical analysis underlying a Fortran program for calculating the proper solutions of the Orr-Sommerfeld system with sufficient accuracy and economy for applying the resonance theory of transition is described. This program covers spacewise growths, rather than timewise growths as in previous computations, of mainly two-dimensional Fourier components of the motion. It employs various innovations providing as much accuracy from efficient single-precision arithmetic as would be obtained from awkward multiple-precision arithmetic in previous calculation schemes. The source programs and some sample calculations, for the proncipal mode of oscillation of the Blasius boundary layer, are included. The Lees-Lin stability equation for compressible flow have been extended to include the terms involving the component of the mean boundary layer flow perpendicular to the flat plate. At Mach 5 this more than doubled the critical Reynolds number. Allowance was then made for the three-dimensional aspect of the disturbance velocity. The final result was to give good agreement with observed data in the lower branch of the neutral stability curve at Mach 2.2 and Mach 5, fair agreement with the upper branch at Mach 2.2 and large discrepancies with the data in the upper branch at Mach 5. Comparison of experimental determined neutral stability curves with those computed by simplified approximations have disagreed considerably at high Mach numbers on the upper branch, even when agreement was fairly good on the lower branch.
Report Availability
Full text available
Date Issued
1966-09
Provenance
Lockheed Martin Missiles & Fire Control
Type
report
Format
1 online resource
Media
AFFDLTR64-184.pdf

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