Pressure fluctuations resulting from shock interactions
| Autor: | M.V. Lowson |
|---|---|
| Rok vydání: | 1968 |
| Předmět: |
Shock wave
Physics Acoustics and Ultrasonics Shock (fluid dynamics) Astrophysics::High Energy Astrophysical Phenomena Mechanical Engineering Acoustics Mechanics Condensed Matter Physics Mach wave Moving shock Physics::Fluid Dynamics symbols.namesake Mach number Mechanics of Materials symbols Oblique shock Bow shock (aerodynamics) Normal shock tables Astrophysics::Galaxy Astrophysics |
| Zdroj: | Journal of Sound and Vibration. 7:380-392 |
| ISSN: | 0022-460X |
| DOI: | 10.1016/0022-460x(68)90137-5 |
| Popis: | High levels of pressure fluctuation have been observed on surfaces beneath shock waves in turbulent flow. These levels contribute substantially to the buffet loadings experienced by aircraft and space vehicles in transonic and supersonic flight. It has usually been suggested that these fluctuations are associated with an oscillating shock phenomenon. However, it is shown here that the interaction between the turbulence and a shock is sufficient to account for the observed fluctuating pressure field. Computations have been performed following the methods of Ribner [2], but explicitly including the near-field pressure terms. It has been found that, for instance, the interaction of turbulence of intensity 0·05 with a typical separation shock at Mach = 2·0 will generate a near-field noise level of 164 dB. The contribution of shock motion, due to turbulence, to surface pressure fluctuations has been studied. The interaction between shocks and sound has been studied following Moore [3]. The predicted magnification of incident sound behind the shock (4·5 dB for a Mach = 2·0 separation shock) is probably sufficient to account for the suggested sensitivity of an oscillating shock to wind tunnel noise. |
| Databáze: | OpenAIRE |
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