Measurement of turbulence transport properties in a supersonic boundary-layer flow using laser velocimeter and hot-wire anemometer techniques

1973 ◽  
Author(s):  
D. JOHNSON ◽  
W. ROSE
Keyword(s):  
Boundary Layer ◽  
Transport Properties ◽  
Boundary Layer Flow ◽  
Supersonic Boundary Layer ◽  
Hot Wire ◽  
Layer Flow ◽  
Turbulence Transport

An instability in supersonic boundary-layer flow over a compression ramp

1995 ◽  
Vol 300 ◽  
pp. 265-285 ◽  
Author(s):  
K. W. Cassel ◽  
A. I. Ruban ◽  
J. D. A. Walker
Keyword(s):  
Boundary Layer ◽  
Boundary Layer Flow ◽  
Streamwise Velocity ◽  
Supersonic Boundary Layer ◽  
Recirculation Region ◽  
Hypersonic Boundary Layer ◽  
Recirculating Flow ◽  
Inflection Points ◽  
Compression Ramp ◽  
Layer Flow

Separation of a supersonic boundary layer (or equivalently a hypersonic boundary layer in a region of weak global interaction) near a compression ramp is considered for moderate wall temperatures. For small ramp angles, the flow in the vicinity of the ramp is described by the classical supersonic triple-deck structure governing a local viscous-inviscid interaction. The boundary layer is known to exhibit recirculating flow near the corner once the ramp angle exceeds a certain critical value. Here it is shown that above a second and larger critical ramp angle, the boundary-layer flow develops an instability. The instability appears to be associated with the occurrence of inflection points in the streamwise velocity profiles within the recirculation region and develops as a wave packet which remains stationary near the corner and grows in amplitude with time.

Micromachined Hot-Wire Boundary Layer Flow Imaging Array

2006 ◽  
Author(s):  
Yingchen Yang ◽  
Saunvit Pandya ◽  
Jack Chen ◽  
Jonathan Engel ◽  
Nannan Chen ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Flight Control ◽  
Boundary Layer Flow ◽  
Sensor Array ◽  
Water Channel ◽  
Sensor Arrays ◽  
Flow Imaging ◽  
Hot Wire ◽  
Threshold Velocity ◽  
Layer Flow

Boundary layer flow imaging can provide real time information for flight control of air vehicles, and collision avoidance and stealth detection of underwater vehicles. High density, micro-scaled sensor arrays based on microfabrication techniques have made it possible to enable these new applications. We report on the development of such a flow sensor array. It is realized by combining surface micromachining and three-dimensional assembly. It consists of a linear array of 16 integrated hot-wire anemometers (HWA) evenly spaced 1 mm apart. Each sensor uses a 400 μm long thermal element (hot-wire) that is made of a thin film nickel/polyimide composite, and is elevated 600 μm above the substrate. Under constant temperature (CT) mode, the threshold velocity sensitivity to water flow is down to 100 μm/s, and the frequency response to dynamic signals is up to 1000 Hz. The capabilities of the sensor array on boundary flow measurement and hydrodynamic wake imaging are demonstrated via wind tunnel and water channel experiments.

Subsonic and Supersonic Boundary-Layer Flow past a Wavy Wall

AIAA Journal ◽  
1972 ◽  
Vol 10 (5) ◽  
pp. 636-642 ◽  
Author(s):  
G. R. INGER ◽  
E. P. WILLIAMS
Keyword(s):  
Boundary Layer ◽  
Boundary Layer Flow ◽  
Supersonic Boundary Layer ◽  
Wavy Wall ◽  
Flow Past ◽  
Layer Flow
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