8. F modeling#
8.1. Characteristics of modeling#
To validate the modeling in a coordinate system different from the global coordinate system, the plate is rotated by \(\mathrm{15,5}°\). This should not change the natural frequencies obtained.
8.2. Characteristics of the mesh#
Number of knots: 122
Number of meshes and types: 100 QUAD8
8.3. Tested sizes and results#
Identification |
Instants |
Reference |
Aster |
% difference |
|
Frequency (mode 4 out of plane) |
44.762 |
43.870 |
—1.993 |
||
Frequency (modes 5 & 6 off plan) |
110.52 |
106.041 |
—4.052 |
||
Frequency (mode 7 out of plane) |
169.08 |
160.055 |
—5.337 |
||
Frequency (Mode 8 in the map) |
193.93 |
193.93 |
193.588 |
—0.176 |
|
Frequency (mode 9 & 10 in the map) |
206.64 |
206.192 |
—0.216 |
8.4. notes#
In*Code_*Aster, the calculated modes are those of rigid bodies: the fourth reference mode is the first mode calculated by*Code_Aster.
Appearance of two flexure modes between reference modes 8 and 9: these are modes 6 and 7 of*Code_Aster.
In the table below we have reported the first 14 natural frequencies found.
Mode No. |
Frequency (\(\mathrm{Hz}\)) |
1 |
43.87 |
2 |
106.04 |
3 |
106.04 |
4 |
160.06 |
5 |
193.59 |
6 |
199.64 |
7 |
200.13 |
8 |
206.19 |
9 |
206.19 |
10 |
219.26 |
11 |
245.68 |
12 |
245.68 |
13 |
249.20 |
14 |
287.99 |