| Title | Compressibility effects in turbulent boundary layers |
| Authors | Cao Yu-Hui Pei Jie Chen Jun She Zhen-Su |
| Affiliation | Peking Univ, Coll Engn, State Key Lab Turbulence & Complex Syst, Beijing 100871, Peoples R China. Univ Calif Los Angeles, Dept Math, Los Angeles, CA 90095 USA. |
| Keywords | CHANNEL FLOW VELOCITY DYNAMICS |
| Issue Date | 2008 |
| Publisher | chinese physics letters |
| Citation | CHINESE PHYSICS LETTERS.2008,25,(9),3315-3318. |
| Abstract | Local cascade (LC) scheme and space-time correlations are used to study turbulent structures and their convection behaviour in the near-wall region of compressible boundary layers at Ma = 0.8 and 1.3. The convection velocities of fluctuating velocity components u (streamwise) and v (vertical) are investigated by statistically analysing scale-dependent ensembles of LC structures. The results suggest that u is convected with entropy perturbations while v with an isentropic process. An abnormal thin layer distinct from the conventional viscous sub-layer is discovered in the immediate vicinity of the wall (y(+) <= 1) in supersonic flows. While in the region 1 < y(+) < 30, streamwise streaks dominate velocity, density and temperature fluctuations, the abnormal thin layer is dominated by spanwise streaks in vertical velocity and density fluctuations, where pressure and density fluctuations are strongly correlated. The LC scheme is proven to be effective in studying the nature of supersonic flows and compressibility effects on wall-bounded motions. |
| URI | http://hdl.handle.net/20.500.11897/316966 |
| ISSN | 0256-307X |
| Indexed | SCI(E) 中国科技核心期刊(ISTIC) 中国科学引文数据库(CSCD) |
| Appears in Collections: | 工学院 湍流与复杂系统国家重点实验室 |
