@Article{MancoFreiFernMend:2015:StCoMi,
author = "Manco, Jhonatan Andr{\'e}s Aguirre and Freitas, Romulo B. and
Fernando, Leandro M. and Mendon{\c{c}}a, Marcio T.",
affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto
de Aeron{\'a}utica e Espa{\c{c}}o (IAE)} and {Instituto de
Aeron{\'a}utica e Espa{\c{c}}o (IAE)} and {Instituto de
Aeron{\'a}utica e Espa{\c{c}}o (IAE)}",
title = "Stability of compressible mixing layers modified by wakes and
jets",
journal = "Procedia IUTAM",
year = "2015",
volume = "14",
pages = "129--136",
keywords = "linear stability analysis, binary free shear layers, direct
numerical simulation.",
abstract = "Binary free shear layers are frequently used as a model to study
the stability of flows relevant in propulsion devices. The
stability behaviour of binary, compressible mixing layer have been
investigated and reported in the literature by many research
groups and detailed description of the stability characteristics
and flow topology have been published. The stability of more
complex free shear layers, such as mixing layers modified by jets
and wakes, has received less attention and a smaller number of
references report on the stability characteristics of such flows.
The availability of advanced numerical techniques as well as
computational power nowadays allow the study of complex flows by
direct numerical simulation. The present investigation is an
extension of previous work on the stability of complex free shear
flows where besides growth rates, wave numbers and frequencies,
the flow topology resulting from the interaction of mixing layers,
jets and wakes are investigated. The results show that, depending
on the jet or wake strength relative to the mixing layer fast and
slow stream velocities, the characteristic Kelvin-Helmholtz
vortices may be enhanced and a more complex vortex distribution
topology results. These vorticity distributions have a significant
effect on the mixture between different species on the upper and
lower stream and the mixing layer to jet species ratio. The effect
of three-dimensional disturbances with spanwise wavenumber
\β * 0 are also considered and the most amplified modes are
determined for a low convective mach number condition. Different
combinations of hydrogen and oxygen on the mixing layer and jets
are considered. For that study the base flow is determined from a
parabolic, variable properties boundary layer code. The results
show that oblique disturbances are more stable than
two-dimensional disturbances but with different strength depending
on the particular binary free shear layer considered.",
doi = "10.1016/j.piutam.2015.03.032",
url = "http://dx.doi.org/10.1016/j.piutam.2015.03.032",
issn = "2210-9838",
language = "en",
urlaccessdate = "04 maio 2024"
}