Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Flow visualization inside a Ranque-Hilsch tube   In this fuid dynamics video we visualize the flow inside a Ranque-Hilsch tube
either with baby powder or with water.

31
The categories of this paper are: ao-sci
22
The categories of this paper are: chao-dyn
34
The categories of this paper are: chem-ph
24
The categories of this paper are: dg-ga
0
The categories of this paper are: hep-ph
12
The categories of this paper are: nucl-th
20
The categories of this paper are: acc-phys
37
The categories of this paper are: supr-con
16
The categories of this paper are: stat
17
The categories of this paper are: q-fin
1
The categories of this paper are: cs
5
The categories of this paper are: gr-qc
28
The categories of this paper are: alg-geom
29
The categories of this paper are: funct-an
21
The categories of this paper are: adap-org
11
The categories of this paper are: hep-lat