Chin. Phys. B ›› 2013, Vol. 22 ›› Issue (1): 14702-014702.doi: 10.1088/1674-1056/22/1/014702
• ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS • 上一篇 下一篇
朱杨柱, 易仕和, 何霖, 田立丰, 周勇为
Zhu Yang-Zhu (朱杨柱), Yi Shi-He (易仕和), He Lin (何霖), Tian Li-Feng (田立丰), Zhou Yong-Wei (周勇为)
摘要: In a Mach 3.8 wind tunnel, both instantaneous and time-averaged flow structures of different scales around a blunt double-cone with or without supersonic film cooling were visualized via nano-tracer planar laser scattering (NPLS), which has a high spatiotemporal resolution. Three experimental cases with different injection mass flux rates were carried out. Lots of typical flow structures were clearly shown, such as shock wave, expansion fan, shear layer, mixing layer, and turbulent boundary layer. The analysis of two NPLS images with an interval of 5 μs revealed the temporal evolution characteristics of flow structures. With matched pressures, the laminar length of the mixing layer was longer than that in the case with a larger mass flux rate, but the full covered region was shorter. Structures like K-H (Kelvin-Helmholtz) vortices were clearly seen in both flows. Without injection, the flow was similar to the supersonic flow over a backward-facing step, and the structures were relatively simpler, and there was a longer laminar region. Large scale structures such as hairpin vortices were visualized. In addition, the results were compared in part with the schlieren images captured by others under the similar conditions.
中图分类号: (Supersonic and hypersonic flows)