Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Frequency lock closed-loop control of a separated flow using visual
  feedback   In this study, a simple model based closed-loop algorithm is used to control
the separated flow downstream a backward-facing step. It has been shown in
previous studies that the recirculation bubble can be minimized when exciting
the shear layer at its natural Kelvin-Helmholtz instability frequency. In this
experiment, the natural shedding frequency is identified through real-time
analysis of 2D velocity fields. Actuation (pulsed jet) is then locked on this
frequency. If flow characteristics stray too far from a set point, shedding
frequency is updated and actuation changed. The present work demonstrates the
efficacy and robustness of this approach in reducing recirculation while
Reynolds number is randomly varied between 1400 and 2800.

6
The categories of this paper are: astro-ph
5
The categories of this paper are: gr-qc
32
The categories of this paper are: atom-ph
15
The categories of this paper are: nucl-ex
19
The categories of this paper are: eess
34
The categories of this paper are: chem-ph
2
The categories of this paper are: math
28
The categories of this paper are: alg-geom
13
The categories of this paper are: quant-ph
22
The categories of this paper are: chao-dyn
9
The categories of this paper are: nlin
4
The categories of this paper are: cond-mat
14
The categories of this paper are: math-ph
26
The categories of this paper are: bayes-an
12
The categories of this paper are: nucl-th
25
The categories of this paper are: patt-sol