Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Energy harvesting efficiency of piezoelectric flags in axial flows   Self-sustained oscillations resulting from fluid-solid instabilities, such as
the flutter of a flexible flag in axial flow, can be used to harvest energy if
one is able to convert the solid energy into electricity. Here, this is
achieved using piezoelectric patches attached to the surface of the flag that
convert the solid deformation into an electric current powering purely
resistive output circuits. Nonlinear numerical simulations in the slender-body
limit, based on an explicit description of the coupling between the fluid-solid
and electric systems, are used to determine the harvesting efficiency of the
system, namely the fraction of the flow kinetic energy flux effectively used to
power the output circuit, and its evolution with the system's parameters. The
role of the tuning between the characteristic frequencies of the fluid-solid
and electric systems is emphasized, as well as the critical impact of the
piezoelectric coupling intensity. High fluid loading, classically associated
with destabilization by damping, leads to greater energy harvesting, but with a
weaker robustness to flow velocity fluctuations due to the sensitivity of the
flapping mode selection. This suggests that a control of this mode selection by
a careful design of the output circuit could provide some opportunities of
improvement for the efficiency and robustness of the energy harvesting process.

33
The categories of this paper are: plasm-ph
20
The categories of this paper are: acc-phys
26
The categories of this paper are: bayes-an
22
The categories of this paper are: chao-dyn
12
The categories of this paper are: nucl-th
36
The categories of this paper are: cmp-lg
0
The categories of this paper are: hep-ph
4
The categories of this paper are: cond-mat
35
The categories of this paper are: mtrl-th
24
The categories of this paper are: dg-ga
16
The categories of this paper are: stat
2
The categories of this paper are: math
10
The categories of this paper are: q-bio
9
The categories of this paper are: nlin
18
The categories of this paper are: econ
17
The categories of this paper are: q-fin