Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Abatement of mixing in shear-free elongationally unstable viscoelastic
  microflows   The addition of minute amounts of chemically inert polyacrylamide polymer to
liquids results in large instabilities under steady electro-osmotic pumping
through 2:1 constrictions, demonstrating that laminar flow conditions can be
broken in electro-osmotic flow of viscoelastic material. By excluding shear and
imposing symmetry we create a platform where only elongational viscoelastic
instabilities, and diffusion, affect mixing. In contrast to earlier studies
with significant shear that found up to orders of magnitude increase in mixing
we find that inclusion of polymers excites large viscoelastic instabilities yet
mixing is reduced relative to polymer-free liquids. The absolute decrease in
mixing we find is consistent with the understanding that adding polymer
increases viscosity while viscoelastic flows progress towards elastic
turbulence, a type of mild (Batchelor) turbulence, and indicates that
electro-osmotic pumped devices are an ideal platform for studying viscoelastic
instabilities without supplementary factors.

20
The categories of this paper are: acc-phys
13
The categories of this paper are: quant-ph
33
The categories of this paper are: plasm-ph
18
The categories of this paper are: econ
23
The categories of this paper are: solv-int
35
The categories of this paper are: mtrl-th
34
The categories of this paper are: chem-ph
19
The categories of this paper are: eess
17
The categories of this paper are: q-fin
3
The categories of this paper are: physics
9
The categories of this paper are: nlin
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
12
The categories of this paper are: nucl-th
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The categories of this paper are: comp-gas
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The categories of this paper are: funct-an