Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A general, three-dimensional fluid dynamics code for stars in binary
  systems   We describe the theory and implementation of a three-dimensional fluid
dynamics code which we have developed for calculating the surface geometry and
circulation currents in the secondaries of interacting binary systems. The main
method is based on an Eulerian-Lagrangian scheme to solve the advective and
force terms in Euler's equation. Surface normalised spherical polar coordinates
are used to allow the accurate modelling of the surface of the star, as is
necessary when free surfaces and irradiation effects are to be considered. The
potential and its gradient are expressed as sums of Legendre polynomials, which
allows a very efficient solution of Poisson's equation. The basic solution
scheme, based on operator splitting, is outlined, and standard numerical tests
are presented.

5
The categories of this paper are: gr-qc
13
The categories of this paper are: quant-ph
34
The categories of this paper are: chem-ph
17
The categories of this paper are: q-fin
26
The categories of this paper are: bayes-an
11
The categories of this paper are: hep-lat
35
The categories of this paper are: mtrl-th
36
The categories of this paper are: cmp-lg
29
The categories of this paper are: funct-an
15
The categories of this paper are: nucl-ex
0
The categories of this paper are: hep-ph
23
The categories of this paper are: solv-int
9
The categories of this paper are: nlin
21
The categories of this paper are: adap-org
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con