Methods for Identifying Key Features in Schlieren Images from Hypersonic Boundary-Layer Instability Experiments

2015 ◽  
Author(s):  
Nathan Shumway ◽  
Stuart J. Laurence
Keyword(s):  
Boundary Layer ◽  
Hypersonic Boundary Layer ◽  
Boundary Layer Instability ◽  
Key Features ◽  
Schlieren Images

An experiment on the stability of hypersonic laminar boundary layers

1960 ◽  
Vol 7 (3) ◽  
pp. 385-396 ◽  
Author(s):  
Anthony Demetriades
Keyword(s):  
Boundary Layer ◽  
Flat Surface ◽  
Hypersonic Boundary Layer ◽  
Natural Disturbances ◽  
Hot Wire ◽  
Amplitude Variation ◽  
Laminar Boundary Layers ◽  
Boundary Layer Instability ◽  
The Stability ◽  
Maximum Amplification

An experimental investigation of the hydrodynamic stability of the laminar hypersonic boundary layer was carried out with the aid of a hot-wire anemometer. The case investigated was that of a flat surface at zero angle of attack and no heat transfer.The streamwise amplitude variation of both natural disturbances and of disturbances artifically excited with a siren mechanism was studied. In both cases it was found that such small fluctuations amplify for certain ranges of frequency and Reynolds number Rθ, and damp for others. The demarcation boundaries for the amplification (instability) zone were found to resemble the corresponding limits of boundary-layer instability at lower speeds. A ‘line of maximum amplification’ of disturbances was also found. The amplification rates and hence the degree of selectivity of the hypersonic layer were found, however, to be considerably lower than those at the lower speeds. The disturbances selected by the layer for maximum amplifications have a wavelength which was estimated to be about twenty times the boundary-layer thickness δ.

Hypersonic Boundary-Layer Instability on a Highly Cooled Cone. Part II: Schlieren Analysis of Boundary-Layer Disturbances

2022 ◽  
Author(s):  
Laura A. Paquin ◽  
Shaun Skinner ◽  
Stuart J. Laurence ◽  
Ahsan Hameed ◽  
David Shekhtman ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Hypersonic Boundary Layer ◽  
Boundary Layer Instability
Sign in / Sign up

Export Citation Format

Share Document