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Accession Number ADA564009
Title Measurements of the Mechanisms of Laminar-Turbulent Transition in the Mach-6 Quiet Tunnel.
Publication Date Feb 2012
Media Count 38p
Personal Author S. P. Schneider
Abstract The Mach-6 tunnel continues to run quiet to moderately high Reynolds numbers. Quiet flow was degraded in 2010 when the throat was opened, but a thorough repolishing of the throat resulted in a significant improvement in performance. Since the nozzle-wall boundary layer remains laminar more than 10 inches downstream of the exit to unit Reynolds numbers near 3.5 million per foot, unprecedented quiet-flow Reynolds numbers can now be achieved on slender models. The tunnel is operated by a single graduate student, with good reliability, and a large amount of data can be obtained during each run using a variety of sensors. Instability and transition measurements were carried out on various models to study the second-mode and crossflow instabilities, the instabilities behind an isolated roughness, the development of second-mode wave packets and turbulent spots, the general effects of roughness and tunnel noise, the effect of tunnel noise on oscillations in a forward-facing cavity, and other phenomena. The research resulted in 17 conference papers, 8 Master's theses and 2 Ph.D. theses. A brief summary is reported here, along with selected highlights.
Keywords Boundary layer
Cross flow
Flow
High rate
Hypersonic flow
Instability
Mach-6 tunnel
Measurement
Models
Noise
Reports
Reynolds number
Theses
Transitions
Turbulence
Waves
Wind tunnels


 
Source Agency Non Paid ADAS
NTIS Subject Category 94K - Laboratory & Test Facility Design & Operation
46B - Fluid Mechanics
Corporate Author Purdue Univ., West Lafayette, IN. School of Aeronautics and Astronautics.
Document Type Technical report
Title Note Final technical rept. 1 Mar 2009-30 Nov 2011.
NTIS Issue Number 1302
Contract Number FA9550-09-1-0191

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