Development of turbulent boundary layer with large density gradients

✍ Scribed by R. Riva; G. Binder; M. Favre-Marinet; J.-L. Harion

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 735 KB
• Volume: 9
• Category: Article
• ISSN: 0894-1777
• DOI: 10.1016/0894-1777(94)90109-0

✦ Synopsis

A hot-wire/film and flow visualization study has been carried out in a turbulent boundary layer. Density differences were generated by injecting different gas mixtures parallel to the wall. Measurements show that the effects of the density ratio S on the mean velocity field are small. On the contrary, dilution of helium injected into an air-helium mixture (density ratio S = 4) is very rapid compared to the case with small density differences (S = 0.88). The friction coefficient is little affected by S, whereas the heat exchange is considerably increased by helium injection in the initial region.