PSI - Issue 25

Wojciech Danek et al. / Procedia Structural Integrity 25 (2020) 19–26 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

22 4

3. Influence of selected parameters of numerical modeling In order to carry out an initial verification of the numerical model, the influence of selected parameters on the obtained results was determined. The considered parameters in this study are the following:  consideration of a layered structure,  boundary conditions,  mesh density. 3.1. Consideration of a layered structure Two different approaches allowing modeling plates made of composite material were analyzed. In the first approach the composite plate was modeled as one layer (Fig. 2a). To improve the accuracy of this approach of modeling, 6 integration points on a thickness were used. A coarse Finite Element Mesh was attributed in order to maintain a reasonable ratio of the element size to the thickness. In the second approach the composite plate was modeled as 10 separate layers (Fig. 2b) that were connected via the contact model. This approach allows taking the presence of a delaminating process into account.

a)

b)

Fig. 2. Two different approach allowing modeling composite plates a) as one layer b) as 10 separate layer.

Based on the results obtained from the numerical simulation it was determined that for the case of modeling the composite plate as one layer, the surface area that was damaged is equal to 196 mm 2 , and for modeling as 10 separate layers, it is equal to 240 mm 2 . In addition to the calculated damaged surface area, maps of von Misses stress for both cases are shown (see Fig. 3).

a)

b)

Fig. 3. Von Misses stress map after the impact for the plate a) modeled as 1 layer b) modeled as 10 separate layers.