Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Stokes flow near the contact line of an evaporating drop   The evaporation of sessile drops in quiescent air is usually governed by
vapour diffusion. For contact angles below $90^\circ$, the evaporative flux
from the droplet tends to diverge in the vicinity of the contact line.
Therefore, the description of the flow inside an evaporating drop has remained
a challenge. Here, we focus on the asymptotic behaviour near the pinned contact
line, by analytically solving the Stokes equations in a wedge geometry of
arbitrary contact angle. The flow field is described by similarity solutions,
with exponents that match the singular boundary condition due to evaporation.
We demonstrate that there are three contributions to the flow in a wedge: the
evaporative flux, the downward motion of the liquid-air interface and the
eigenmode solution which fulfils the homogeneous boundary conditions. Below a
critical contact angle of $133.4^\circ$, the evaporative flux solution will
dominate, while above this angle the eigenmode solution dominates. We
demonstrate that for small contact angles, the velocity field is very
accurately described by the lubrication approximation. For larger contact
angles, the flow separates into regions where the flow is reversing towards the
drop centre.

17
The categories of this paper are: q-fin
28
The categories of this paper are: alg-geom
21
The categories of this paper are: adap-org
19
The categories of this paper are: eess
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The categories of this paper are: astro-ph
2
The categories of this paper are: math
30
The categories of this paper are: q-alg
11
The categories of this paper are: hep-lat
7
The categories of this paper are: hep-th
34
The categories of this paper are: chem-ph
18
The categories of this paper are: econ
29
The categories of this paper are: funct-an
10
The categories of this paper are: q-bio
0
The categories of this paper are: hep-ph
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The categories of this paper are: dg-ga
22
The categories of this paper are: chao-dyn