Abstr:UFR 3-32
Planar shock-wave boundary-layer interaction
Semi-confined Flows
Underlying Flow Regime 3-32
Abstract
The interaction between a shock wave and a boundary layer remains an
issue for both applications and basic research. In aeronautical
situations, such interactions are at the origin of unsteadiness which
may be detrimental for air frames and mechanical structures. The
understanding of such phenomena is not always clear because the
frequencies involved in the unsteadiness are much below any other
characteristic frequency in the flow (see Dolling 2001
and Smits and Dussauge 2006 for reviews).
Only a few interpretations have been
proposed, although recent attempts seem to offer more comprehensive
views (see Dupont, Debiève, Dussauge 2011 for example).
A severe test
case is proposed in the European program UFAST (Unsteady eFfects of
shock wAve induced SeparaTion) to illustrate this problem: the
reflection of an oblique shock on the turbulent boundary layer of a flat
plate at a Mach number of 2.25, at different angles of deviation
producing different cases of separation. This well documented experiment
is presented, including mean and turbulent flow measurements together
with spectral measurements to determine the dominant frequencies of the
unsteadiness.
Of course a RANS model can only provide a global description
of mean quantities. More advanced models like LES or DES have the
ability to capture the unsteadiness. Comparisons with LES and DES
numerical simulations are presented and discussed, and best practice
guidelines are proposed. These studies are available in the UFAST
database, as published in Doerffer 2009
and in Doerffer et al. 2010.
Contributed by: Jean-Paul Dussauge (*), P. Dupont (*) , N. Sandham (**), E. Garnier (***) — (*) Aix-Marseille Université, and Centre National de la Recherche Scientifique UM 7343, (**) University of Southampton, (***) ONERA/DAAP, Meudon, France
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