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Y. Liu et al.
energy of the Lamb wave with the frequency f propagating the same distance in the
stiffened panel and the flat panel, which can eliminate the influence of propagation
distance and measure the effect of stiffeners more accurately. The energy ratio is
given by (14.3).
E R = F R
2
S /F R
2
P
(14.3)
where F R S represents the frequency response of the Lamb wave in the stiffened panel
and F R P represents the frequency response of the Lamb wave after propagating the
same distance in the flat panel.
14.3 Finite Element Simulation Model
In this paper, ABAQUS finite element simulation software is used to study the Lamb
wave signal propagation law in stiffened panels. The ABAQUS software has a good
simulation effect on the non-linear change of signals. Compared with the threedimensional model, the two-dimensional finite element simulation parameters are
simpler and more efficient. It is more suitable for multi-group control experiments
with control variables. Therefore, the two-dimensional finite element simulation
models were established based on the thickness, stiffener width and height and of the
stiffened panels used in the spacecraft. The schematic diagram of the finite element
model of stiffened panels with two stiffeners is shown in Fig. 14.2. The positions of
each point in the model are recorded in Cartesian coordinate system.
The size of the panel structure is 2000 mm × 3 mm, and the material is 5A06
magnesium-aluminum alloy. The bottom edge of the panel coincides with the x-axis,
and the axis of symmetry perpendicular to the bottom edge coincides with the y-axis.
The height of stiffener is 22 mm, the width is 4 mm, and the spacing between the
adjacent two stiffeners is 50 mm.
Fig. 14.2 The schematic diagram of the finite element model of stiffened panels with two stiffeners
Y. Liu et al.
energy of the Lamb wave with the frequency f propagating the same distance in the
stiffened panel and the flat panel, which can eliminate the influence of propagation
distance and measure the effect of stiffeners more accurately. The energy ratio is
given by (14.3).
E R = F R
2
S /F R
2
P
(14.3)
where F R S represents the frequency response of the Lamb wave in the stiffened panel
and F R P represents the frequency response of the Lamb wave after propagating the
same distance in the flat panel.
14.3 Finite Element Simulation Model
In this paper, ABAQUS finite element simulation software is used to study the Lamb
wave signal propagation law in stiffened panels. The ABAQUS software has a good
simulation effect on the non-linear change of signals. Compared with the threedimensional model, the two-dimensional finite element simulation parameters are
simpler and more efficient. It is more suitable for multi-group control experiments
with control variables. Therefore, the two-dimensional finite element simulation
models were established based on the thickness, stiffener width and height and of the
stiffened panels used in the spacecraft. The schematic diagram of the finite element
model of stiffened panels with two stiffeners is shown in Fig. 14.2. The positions of
each point in the model are recorded in Cartesian coordinate system.
The size of the panel structure is 2000 mm × 3 mm, and the material is 5A06
magnesium-aluminum alloy. The bottom edge of the panel coincides with the x-axis,
and the axis of symmetry perpendicular to the bottom edge coincides with the y-axis.
The height of stiffener is 22 mm, the width is 4 mm, and the spacing between the
adjacent two stiffeners is 50 mm.
Fig. 14.2 The schematic diagram of the finite element model of stiffened panels with two stiffeners