## 6 Simulation Results
Here, all considered core configurations were in the range of 75-80%, as seen in Figure 20. For this reason, the opposing  
Figure 15.0 Honeycomb cores: normalized maximum values for displacement \(u_{3,\text{bot}}\) and reaction force \(\text{RF}_{3}\). Figure 15.1 Honeycomb cores: normalized maximum values for displacement \(u_{3,\text{top}}\) and displacement ratio \(u_{3,\text{top}}/u_{3,\text{bot}}\). cover surfaces retained most of their initial distance (see also Appendix A). Only the sandwich construction with square honeycombs displayed a somewhat softer behavior. In the auxetic variants, larger cell support widths tended to lead to increases in compliance and deformations within the core area. The development of the dissipated energy supports this statement, as shown in Figure 15.2 Here, a clear increase with increases in cell size was observed. In total, almost twice as much energy was dissipated in all topologies compared to the reference plate during the entire observation period. Due to its robust core structure, the honeycomb exhibited the lowest dissipation capacity, with a factor of 1.85. With the conventional hexagonal honeycomb, this also led to an almost undiminished pulse transmission and peak load on the substructure; see Figure 15.3 The use of auxetic cells, on the other hand, reduced the maximum occurring load by up to 25%. With a load reduction of about 20%, the isogrid core also had an advantage over the monolithic panel. Figure 22 illustrates at a glance the type-related differences between the unilaterally open prismatic cores and the previous honeycomb designs. The displacements of the bottom cover surfaces all exceeded the reference value, including, in one case, by up to 40%. Only the isogrid and two auxetic variants (No. 19 and No. 21) were on par with the monolithic reference panel. The displacements of the upper surface were also much more pronounced and, in some cases, more than twice that of the reference plate; see Figure 15.4 Both the non-auxetic (No. 8-17) and the prismatic variants (No. 18-21), in contrast to the honeycomb cores, were primarily subjected to bending stress under the given load. This is evident in the reduced displacement ratio of the lower to the upper surface. In principle, this type of core structure is rather soft and exhibits considerable deformations as well as plastic changes in shape. Figure 15.5 Honeycomb cores: normalized maximum values for plastic dissipation energy. Figure 15.6 Prismatic cores: normalized maximum values for displacement \(u_{\rm 3,hot}\) and reaction force RF\({}_{3}\). The plastic energy dissipations are correspondingly higher. With factors between 2.8 and 3.1, the prismatic variants not only surpassed the performance of the reference panel but also that of the sandwich components with honeycomb cores; see Figure 15.7 The geometries with the highest residual membrane stiffnesses (I-core and square honeycomb 2L/4L) showed significantly lower levels of plastic deformation and, consequently, dissipated less energy. Apart from these two geometries, the considered prismatic core topologies reduced the peak load transmitted to the support structure by about 60% on average, with the Y-core structure reducing it by more than 70%; see Figure 15.8  
With regard to the desired mechanical properties, i.e., low levels of deformation and acceleration on the side facing away from the load, a conflict of objectives arises; lower stress on the adjacent components simultaneously ensures a higher energy dissipation capacity. Obviously, core topologies that are predominantly subjected to bending stress tend to display a significant reduction in the resulting load on the adjacent components. However, at the same time, these cores exhibit comparatively high levels of deformation of the bottom side. Please note that the results for the sandwich structure with a four-layered auxetic pattern (No. 19) do not match this observation. In this study, the deflections on the bottom cover surface did not differ from those of the monolithic panel of the same mass.