PSI - Issue 53

A. Neto et al. / Procedia Structural Integrity 53 (2024) 338–351

349

12

Alexandre de Oliveira Neto / Structural Integrity Procedia 00 (2019) 000–000

10 12 14 16

L1 L2

13,56

10,25

0 2 4 6 8

5,13

4,06

Total Energy [J]

0

2

4

6

8

10

12

14

16

Time [ms]

Fig. 15. L1 and L2 total energy-time graph with visible external damage

L1 retains 24 % of elastic energy, being the lowest value of the lot for L1, meaning the vulnerability of the tube layup is more compromised than ever due to a high energy impact. Consistently, L2 also records its lowest elastic energy value, 21 %. 3.4. Max principal strain layer analysis The "max principal strain" is the largest of these three principal strains at a given point in the model. It provides information about the maximum deformation or stretching experienced by the material at that location. In order to correlate the impact energy level with the strain results, every layer of both layups was showcased in in the state of visible external damage (most energy) to evaluate the influence of the layer orientation on being subjected to strain, in the moment of the most displacement regarding the impactor. Blue means no strain and red means maximum strain.

Fig. 16. Top view of max principal strain layer analysis of L1

Fig. 16 show the variations of strain over L1 layup, where the order is from left to right as it is from the most inboard to the most outboard layer. There is a tendency for the strain to evolve in the opposite direction of the fibre orientation. Except, some layers do not show that same relation. The potential cause for this is that each layer has its moment where the previous conclusion is very apparent.