PSI - Issue 8

L. Landi et al. / Procedia Structural Integrity 8 (2018) 3–13 L. Landi et al. / Structural Integrity Procedia 00 (2017) 000 – 000

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Table 7. Geometry of the central volume of the target Mass [kg]

Dimension of central volume of target [mm 3 ]

0.625 1.250 2.500

50 x 50 x 3 60 x 60 x 3 65 x 65 x 3

Due to 3D model it is not possible to perform a full mesh at 0.1 mm of size, as we desired for the results already shown by Landi and Amici (2016), because of the long elapsed time of every numerical simulation. Some preliminary numerical test were performed to test convergence of the results and refined mesh of 0.5 mm gives excellent results for those virtual tests. Elements of this “refined volume” of the target have a dimension of 0.5 mm. The same size of the mesh is set for the faces of the projectile for which contact with the target is predicted. All the not directly impacting volumes of the target and projectile have elements of 5 mm (Figure 5).

Fig. 4. Critical and penetration energy by Mewes (2000) for impacts on steel DC01 thick 3 mm

For more detailed information on models settings see Landi and Amici (2016).

Fig. 5. Mesh of the model on the refined volume

Mesh of size greater than 0.5 mm on impacting parts of the body gives non-physical results (different and not experimental “shape” of the penetration behaviour) and shall not be used.