NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Collections About News Help Login
Back to Results
A nonlinear structural concept for compliant wallsTwo mechanisms of drag reduction for flow over flat plates were investigated. The first mechanism employs Bushnell's hypothesis that compliant walls produce drag reduction by interfering with the formation of the turbulent spots in a turbulent boundary layer. It is shown that the amplitudes and frequencies of compliant wall motions for drag reduction might be achieved by using slightly curved walls and the resulting large amplitude motions of snap buckling. A simple structural model of an arch is used in the analysis, and an asymptotic method is developed. The required wall motions can be obtained by using materials like mylar. In addition, the delay of transition from laminar to turbulent flow by driven walls was studied for Poiseuille channel flow. The walls are driven by a periodic traveling wave. A significant increase in the transitional Reynolds number is obtained by appropriately prescibing the wavelength and phase velocity of the wall motion. Previously developed asymptotic methods are used in the analysis.
Document ID
19830002791
Acquisition Source
Legacy CDMS
Document Type
Contractor Report (CR)
Authors
Reiss, E. L. (Applied Inst. of Mathematics, Inc. Evanston, IL, United States)
Date Acquired
September 4, 2013
Publication Date
October 1, 1982
Publication Information
Publisher: NASA
Subject Category
Aerodynamics
Report/Patent Number
NAS 1.26:3628
NASA-CR-3628
Accession Number
83N11061
Funding Number(s)
CONTRACT_GRANT: NAS1-14717
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

Related Records

There are no records associated with this record.
No Preview Available