Abstract
Results are presented from an experimental investigation of Mach number effects on entrainment and mixing in a supersonic, planar, turbulent, bluff-body wake formed by a two-dimensional slot jet nozzle aligned with two different Mach number free stream produced by Mach 2.0 and Mach 3.0 nozzles. Planar laser Mie scattering (PLMS) and shadowgraph imaging are combined with pitot and static pressure measurements to examine the mean flow scaling laws and the instantaneous structure of the flow fields. Results for both flows show classical vortex street-like large-scale structures in the wake far field, where the relative Mach numbers have decreased to clearly subsonic values, and the growth rates and velocity decays in the near field followed the characteristic (δ/u>) - (x/u)1/2 and (u/U) ~ (x/u)~l/2 scaling of incompressible planar turbulent wakes. These scaling constants agreed with values for forced incompressible wakes for the Mach 2 case, while those for the Mach 3 case agreed with unforced values, presumably due to the potential existence of "subsonic path". Moreover the interaction of reflected expansion waves with the large-scale vortical structures in the wake appeared to increase the growth rate drastically for both flows which may be attributable to its "self-exited forcing mechanism".
| Original language | English (US) |
|---|---|
| Title of host publication | 38th Aerospace Sciences Meeting and Exhibit |
| State | Published - 2000 |
| Externally published | Yes |
| Event | 38th Aerospace Sciences Meeting and Exhibit 2000 - Reno, NV, United States Duration: Jan 10 2000 → Jan 13 2000 |
Other
| Other | 38th Aerospace Sciences Meeting and Exhibit 2000 |
|---|---|
| Country/Territory | United States |
| City | Reno, NV |
| Period | 1/10/00 → 1/13/00 |
ASJC Scopus subject areas
- Space and Planetary Science
- Aerospace Engineering