Abstract
The effect of surface roughness on the shock transition over flat wedges
in quasi-stationary flows and concave and convex wedges in truly
nonstationary flows is investigated experimentally. Saw-toothed
roughnesses are used for flat wedges. Sand paper provides the surface
roughness for the curved wedges. The experiments are carried out on a 40
mm x 80 mm shock tube equipped with a double exposure holographic
interferometer. The incident shock Mach number range is 1.04-4.0 for
nitrogen or dry air. For the curved wedges, the shock transition angles
are determined by means of a streak camera technique with curved slits.
It is found that the shock transition angles decrease with increasing
surface roughness. For a flat wedge of 0.8 mm surface roughness, the
transition angle is 10 deg smaller than that for a smooth flat wedge for
stronger shocks. The experimental results are explained by reffering to
a shock polar.
Original language | English |
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Pages (from-to) | 326-334 |
Journal | In: Shock tubes and waves; Proceedings of the Thirteenth International Symposium, Niagara Falls, NY, July 6-9, 1981. (A83-26126 10-34) Albany, NY, State University of New York Press, 1982 |
State | Published - 1982 |
Externally published | Yes |
Keywords
- Oblique Shock Waves
- Shock Wave Propagation
- Surface Roughness Effects
- Wave Reflection
- Wedge Flow
- Holographic Interferometry
- Mach Number
- Shock Tubes
- Streak Cameras
- Wave Diffraction