Abstract:
We present an overview and recent understanding of
accelerated inhomogeneous flows, e.g.
shockaccelerated interfaces or RichtmyerMeshkov
flows.^{1,2} We use the vortex paradigm^{1}
and the visiometric approach^{2}
and apply them to the shockaccelerated onemode,
smallamplitude perturbed planar configuration and
cylinder in two dimensions and focus on scaling with
respect to Atwood number.
We quantify phenomena to validate simulations and
create models involving coherent spacetime events.
We emphasize
our recent^{ }work,^{38} including:
finite, initial interfacial gradients (which carry
the initially deposited circulation) and their
subsequent steepening; vortex induced,
secondary baroclinic circulation generation which
creates unstable vortex bilayers that
dominate at intermediate times; vortex bilayer
rollup and the appearance of “vortex projectiles”
(dipolarlike structures) and turbulent domains
which drive the mixing of species; possible
finitetime illposedness; and applicability of a
dipolar incompressible pointvortex model for
amplitude growth. All these events occur in an
essentially incompressible flow, if the initial
shock has M < 1.5. Finally, we discuss the
applicability of these ideas to recent high
resolution RayleighTaylor simulations. ^{
9,10}
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