Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spectral Model of Non-Stationary, Inhomogeneous Turbulence   We compare results from a spectral model for non-stationary, inhomogeneous
turbulence (Besnard et al., Theor. Comp. Fluid. Dyn., vol. 8, pp 1-35, 1996)
with Direct Numerical Simulation (DNS) data of a shear-free mixing layer (SFML)
(Tordella et al., Phys. Rev. E, vol. 77, 016309, 2008). The SFML is used as a
test case in which the efficacy of the model closure for the physical-space
transport of the fluid velocity field can be tested in a flow with
inhomogeneity, without the additional complexity of mean-flow coupling. The
model is able to capture certain features of the SFML quite well for
intermediate to long-times, including the evolution of the mixing-layer width
and turbulent kinetic energy. At short-times, and for more sensitive statistics
such as the generation of the velocity field anisotropy, the model is less
accurate. We present arguments, supported by the DNS data, that a significant
cause of the discrepancies is the local approximation to the intrinsically
non-local pressure-transport in physical-space that was made in the model, the
effects of which would be particularly strong at short-times when the
inhomogeneity of the SFML is strongest.

7
The categories of this paper are: hep-th
30
The categories of this paper are: q-alg
11
The categories of this paper are: hep-lat
5
The categories of this paper are: gr-qc
1
The categories of this paper are: cs
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas
19
The categories of this paper are: eess
4
The categories of this paper are: cond-mat
10
The categories of this paper are: q-bio
23
The categories of this paper are: solv-int
15
The categories of this paper are: nucl-ex
16
The categories of this paper are: stat
33
The categories of this paper are: plasm-ph
9
The categories of this paper are: nlin
0
The categories of this paper are: hep-ph