Experimental study of a separating, reattaching, and redeveloping flow over a smoothly contoured ramp

✍ Scribed by Simon Song; David B DeGraaff; John K Eaton

• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 358 KB
• Volume: 21
• Category: Article
• ISSN: 0142-727X
• DOI: 10.1016/s0142-727x(00)00039-4

✦ Synopsis

A turbulent boundary layer that separates, reattaches, and redevelops over a smoothly contoured ramp and a downstream ¯at plate has been examined. In order to resolve the ¯ow in the viscous sublayer, a custom-built, two-dimensional LDA with a very high resolution was used. A small separation bubble occurred over the trailing edge of the ramp. The v H v H and Àu H v H Reynolds stress components increased rapidly in the adverse pressure gradient boundary layer, and developed large outer layer peaks aligned with the in¯ection point in the mean velocity pro®le. The high stress levels were nearly unchanged by the reattachment process, decaying only after the mean velocity pro®le recovered and outer-layer production dropped. A key feature is that the inner layer recovered relatively quickly to a typical turbulent boundary layer in the redeveloping region, while the outer layer recovery was retarded by the large eddies generated in the separation region.