Regions and transitions of nonstationary oblique shock-wave diffractions in perfect and imperfect gases
Abstract
The diffraction of shock waves in perfect and imperfect nitrogen and argon by sharp compressive corners was investigated analytically and experimentally. It is shown that seven shock-wave diffraction domains exist in nitrogen and six in argon. The domains consisted of the four well-known shock wave reflections: regular reflection, single Mach, and double-Mach reflections. All the transition boundaries between these regions were established analytically and substantiated by experimental results. Over 100 experiments were conducted in hypervelocity shock tube equipped with a 23 cm dia field of view Mach-Zehnder interferometer equipped with a dual-frequency laser light source. It is shown that real gas effects have a significant influence on the size of the regions and their transition boundaries. Some comparison between steady and nonstationary reflections are made and discussed. Isopycnics as well as density distributions along the wedge surface are presented for the various diffraction processes and their differences and similarities are discussed.
- Publication:
-
NASA STI/Recon Technical Report N
- Pub Date:
- August 1978
- Bibcode:
- 1978STIN...7913307B
- Keywords:
-
- Argon;
- Corners;
- Nitrogen;
- Shock Waves;
- Wave Diffraction;
- Compressible Flow;
- Mach Reflection;
- Shock Tubes;
- Wave Reflection;
- Fluid Mechanics and Heat Transfer