Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Velocity and Heat Flow in a Composite Two Fluid System   We describe the stress energy of a fluid with two unequal stresses and heat
flow in terms of two perfect fluid components. The description is in terms of
the fluid velocity overlap of the components, and makes no assumptions about
the equations of state of the perfect fluids. The description is applied to the
metrics of a conformally flat system and a black string.

29
The categories of this paper are: funct-an
8
The categories of this paper are: hep-ex
10
The categories of this paper are: q-bio
18
The categories of this paper are: econ
23
The categories of this paper are: solv-int
7
The categories of this paper are: hep-th
17
The categories of this paper are: q-fin
9
The categories of this paper are: nlin
32
The categories of this paper are: atom-ph
26
The categories of this paper are: bayes-an
11
The categories of this paper are: hep-lat
1
The categories of this paper are: cs
37
The categories of this paper are: supr-con
21
The categories of this paper are: adap-org
36
The categories of this paper are: cmp-lg
22
The categories of this paper are: chao-dyn