This progress report is a series of overviews outlining experiments on the flow physics of confluent boundary layers for high-lift systems. The research objectives include establishing the role of confluent boundary layer flow physics in high-lift production; contrasting confluent boundary layer structures for optimum and non-optimum C(sub L) cases; forming a high quality, detailed archival data base for CFD/modelling; and examining the role of relaminarization and streamline curvature. Goals of this research include completing LDV study of an optimum C(sub L) case; performing detailed LDV confluent boundary layer surveys for multiple non-optimum C(sub L) cases; obtaining skin friction distributions for both optimum and non-optimum C(sub L) cases for scaling purposes; data analysis and inner and outer variable scaling; setting-up and performing relaminarization experiments; and a final report establishing the role of leading edge confluent boundary layer flow physics on high-lift performance

Nelson, R. C.

Thomas, Flint O.

English

NASA Technical Reports Server

NASA-CR-199974
Annual Progress Report '
Submitted to the Low Speed Aerodynamic Branch
NASA Ames Research Center
Moffett Field, CA
for
NASA Grant NAG2-905
entitled
"An Experimental Investigation of the Flow Physics
of High-Lift Systems"
for the period
March - December 1995
by
Drs. Flint O. Thomas and R. C. Nelson
Hessert Center for Aerospace Research
Department of Aerospace and Mechanical Engineering
University of Notre Dame
Notre Dame, IN 46556
December 20,1995
(NASA-CR-199974) AN EXPERIMENTAL N96-19519
INVESTIGATION OF THE FLOW PHYSICS
OF HIGH-LIFT SYSTEMS Annual Report,
Mar. - Dec. 1995 (Notre Dame Unclas
Univ.) 33 p
G3/02 0101207
https://ntrs.nasa.gov/search.jsp?R=19960014061 2020-06-16T04:42:02+00:00Z
Annual Progress Report
Submitted to the Low Speed Aerodynamic Branch
NASA Ames Research Center
Moffett Field, CA
for
NASA Grant NAG2-905
entitled
"An Experimental Investigation of the Flow Physics
of High-Lift Systems"
for the period
March - December 1995
by
Drs. Flint O. Thomas and R. C. Nelson
Hessert Center for Aerospace Research
Department of Aerospace and Mechanical Engineering
University of Notre Dame
Notre Dame, IN 46556
December 20,1995
Annual Progress Report
Submitted to the Low Speed Aerodynamic Branch
NASA Ames Research Center
Moffett Field, CA
for
NASA Grant NAG2-905
entitled
"An Experimental Investigation of the Flow Physics
of High-Lift Systems"
for the period
March - December 1995
by
Drs. Flint O. Thomas and R. C. Nelson
Hessert Center for Aerospace Research
Department of Aerospace and Mechanical Engineering
University of Notre Dame
Notre Dame, IN 46556
December 20,1995
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gap 15 mm
Overhang 10 mm
1.2
1.19
1.18
1.17
1.16
1.15
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CL
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Variation of Lift Coefficient with Slat Gap
Figure 1
1.00
CASE 1
CASE 2
CASE 3
CASE 4
0.0 1.0 2.0
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tt = 10.0°
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with primary airfoil
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Condition of
early confluence
Point of confluence
farther aft: optimum
Cl case
Separation bubble
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leading edge
Separation at
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1.25
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1
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An experimental investigation of the flow physics of high-lift systems

Abstract

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