Transition in supersonic mixing flows

Journal Article · Tue Jan 01 04:00:00 EST 1980 · AIAA Pap.; (United States)

DOI:https://doi.org/10.2514/6.1980-276· OSTI ID:6936561

Babu, B S; Jones, E; Anderson, Jr, J D

An analysis of the flow of a perfect gas from a nozzle bank with exit conditions characteristic of downstream mixing lasers is presented. For the normal exit conditions, turbulent flow may occur with enhanced mixing and increased laser performance. The Saffman-Wilcox (1974) two-equation turbulence model was applied to the time-dependent, two-dimensional Reynolds equations, and MacCormack's (1969) time-dependent finite-difference method was used to calculate the flow downstream of the nozzle exit plane between the centerlines of two adjacent nozzles. It was shown that a higher level of turbulence in the streams will produce enhanced mixing, and the introduction of fluctuating inlet conditions has a small effect on mixing. Transition to a turbulent flow for steady inlet conditions occurs in agreement with pipe and channel flow data after transition, the mean velocity, temperature, and pressure gradients were very small. Finally, it was shown that the turbulence decay downstream was similar to the decay of isotropic turbulence produced by grids.

• Research Organization: Maryland, University, College Park, Md.
• OSTI ID: 6936561
• Journal Information: AIAA Pap.; (United States), Journal Name: AIAA Pap.; (United States) Vol. 80-0276; ISSN AAPRA
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420400* -- Engineering-- Heat Transfer & Fluid Flow
BOUNDARY LAYERS
BOUNDARY-VALUE PROBLEMS
DISPERSIONS
FLUID FLOW
GAS FLOW
LAMINAR FLOW
LASER CAVITIES
LASERS
LAYERS
MIXTURES
NOZZLES
SUPERSONIC FLOW
TRANSITION FLOW
TURBULENT FLOW
UNSTEADY FLOW