PSI - Issue 25

178 P.N. Lymperopoulos et al. / Procedia Structural Integrity 25 (2020) 172–179 Panagiotis N. Lymperopoulos, Efstathios E. Theotokoglou, Ioannis A. Antoniadis / Structural Integrity Procedia 00 (2019) 000–000 7 For the di ff erent diameters (D, d), for a pentamode of height 4 ∗ a, the results obtained can be seen in Figures (8, 9). The results in Figure (9) are presented in a logarithmic diagram.

Fig. 8. Force at nodes at the bottom of the pentamode Material : Titanium alloy

Fig. 9. Calculation of G c

G r , Material : Titanium alloy

From figure (9), the optimum dimensions of D, d diameters, which have similar behaviour with isolators, are between D = 1.32, d = 1.188 and D = 1.32 and d = 1.056.