Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Onset and universality of drag reduction in the turbulent Kolmogorov
  flow   We investigate the phenomenon of drag reduction in a viscoelastic fluid model
of dilute polymer solutions. By means of direct numerical simulations of the
three-dimensional turbulent Kolmogorov flow we show that drag reduction takes
place above a critical Reynolds number $Re_c$. An explicit expression for the
dependence of $Re_c$ on polymer elasticity and diffusivity is derived. The
values of the drag coefficient obtained for different fluid parameters collapse
onto a universal curve when plotted as a function of the rescaled Reynolds
number $Re/Re_c$. The analysis of the momentum budget allows to gain some
insight on the physics of drag reduction, and suggests the existence of a
maximum drag reduction asymptote.

17
The categories of this paper are: q-fin
25
The categories of this paper are: patt-sol
6
The categories of this paper are: astro-ph
36
The categories of this paper are: cmp-lg
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
28
The categories of this paper are: alg-geom
35
The categories of this paper are: mtrl-th
31
The categories of this paper are: ao-sci
4
The categories of this paper are: cond-mat
24
The categories of this paper are: dg-ga
29
The categories of this paper are: funct-an
33
The categories of this paper are: plasm-ph
14
The categories of this paper are: math-ph
10
The categories of this paper are: q-bio
19
The categories of this paper are: eess