Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: A Volume-of-Fluid method for variable-density, two-phase flows at
  supercritical pressure
9
The categories of this paper are: nlin
5
The categories of this paper are: gr-qc
37
The categories of this paper are: supr-con
32
The categories of this paper are: atom-ph
18
The categories of this paper are: econ
22
The categories of this paper are: chao-dyn
11
The categories of this paper are: hep-lat
2
The categories of this paper are: math
19
The categories of this paper are: eess
28
The categories of this paper are: alg-geom
12
The categories of this paper are: nucl-th
23
The categories of this paper are: solv-int
30
The categories of this paper are: q-alg
10
The categories of this paper are: q-bio
7
The categories of this paper are: hep-th
8
The categories of this paper are: hep-ex