Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nonlinearity in Oscillatory Flow over Sand Ripple   In this report, We investigated the nonlinear phenomena in the study of flow
dynamics of velocity component. In our studies, we observed nonlinear term in
the vertical component of velocity by vittori et al \cite{vit} The time series
simulation of vertical component which increases with Reynold stress value. We
developed direct numerical simulation under two dimensional grid system to
study the flow dynamics and vorticity parameter. Flow pattern and flow dynamics
near wavy boundary wall in the victinity of ripple bottom was readdressed under
direct numerical simualtion(DNS) framework.

24
The categories of this paper are: dg-ga
36
The categories of this paper are: cmp-lg
22
The categories of this paper are: chao-dyn
30
The categories of this paper are: q-alg
23
The categories of this paper are: solv-int
5
The categories of this paper are: gr-qc
25
The categories of this paper are: patt-sol
0
The categories of this paper are: hep-ph
26
The categories of this paper are: bayes-an
37
The categories of this paper are: supr-con
29
The categories of this paper are: funct-an
10
The categories of this paper are: q-bio
12
The categories of this paper are: nucl-th
27
The categories of this paper are: comp-gas
17
The categories of this paper are: q-fin
4
The categories of this paper are: cond-mat