Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Boundary-layer control by electric fields: A feasibility study   A problem of great concern in aviation and submarine propulsion is the
control of the boundary layer and, in particular, the methods to extend the
laminar region as a means to decrease noise and fuel consumption. In this paper
we study the flow of air along an airfoil when a layer of ionized gas and a
longitudinal electric field are created in the boundary layer region. By
deriving scaling solutions and more accurate numerical solutions we discuss the
possibility of achieving significant boundary layer control for realistic
physical parameters. Practical design formulas and criteria are obtained. We
also discuss the perspectives for active control of the laminar-to-turbulent
transition fluctuations by electromagnetic field modulation.

35
The categories of this paper are: mtrl-th
12
The categories of this paper are: nucl-th
25
The categories of this paper are: patt-sol
18
The categories of this paper are: econ
2
The categories of this paper are: math
30
The categories of this paper are: q-alg
4
The categories of this paper are: cond-mat
24
The categories of this paper are: dg-ga
22
The categories of this paper are: chao-dyn
10
The categories of this paper are: q-bio
37
The categories of this paper are: supr-con
16
The categories of this paper are: stat
0
The categories of this paper are: hep-ph
34
The categories of this paper are: chem-ph
1
The categories of this paper are: cs
36
The categories of this paper are: cmp-lg