Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Unsteady control of supersonic turbulent cavity flow based on resolvent
  analysis   We use resolvent analysis to determine an unsteady active control setup to
attenuate pressure fluctuations in turbulent supersonic flow over a rectangular
cavity with a length-to-depth ratio of 6 at a Mach number of 1.4 and a Reynolds
number based on cavity depth of 10,000. Large-eddy simulations (LES) and
dynamic modal decomposition (DMD) of the supersonic cavity flow reveal the
dominance of two-dimensional Rossiter modes II and IV. These predominantly
two-dimensional vortical structures generate high-amplitude unsteadiness over
the cavity through trailing-edge impingement and create oblique shock waves by
obstructing the freestream. To disrupt the undesired formation of vortical
structures, we introduce three-dimensional unsteady forcing along the cavity
leading edge to generate streamwise vortical structures. Resolvent analysis
with respect to the time-averaged base flow is leveraged to determine the
optimal combination of forcing frequency and spanwise wavenumber. Instead of
selecting the most amplified resolvent forcing modes, we seek the combination
of control parameters that yields sustained amplification of the primary
resolvent-based kinetic energy distribution over the entire length of the
cavity. The sustained amplification is critical to ensure that the selected
forcing input remains effective to prevent the formation of the large spanwise
vortices. This resolvent-analysis-based flow control guideline is validated
with a number of companion LES of the controlled cavity flows. The optimal
control setup is verified to be the most effective in reducing the pressure
root-mean-square level up to 52% along the aft and bottom cavity walls compared
to the baseline cavity flow. The present flow control guideline derived from
resolvent analysis should be applicable to flows that require the actuation
input to remain effective over an extended region of interest.

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The categories of this paper are: atom-ph
8
The categories of this paper are: hep-ex
23
The categories of this paper are: solv-int
12
The categories of this paper are: nucl-th
9
The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th
6
The categories of this paper are: astro-ph
7
The categories of this paper are: hep-th
18
The categories of this paper are: econ
27
The categories of this paper are: comp-gas
11
The categories of this paper are: hep-lat
37
The categories of this paper are: supr-con
4
The categories of this paper are: cond-mat
24
The categories of this paper are: dg-ga
10
The categories of this paper are: q-bio
16
The categories of this paper are: stat