Simultaneous Shape and Stacking Sequence Optimization of Laminated Composite Free-Form Shells Using Multi-Island Genetic Algorithm

Table 5

Optimization results of the second phase optimization for Shell 1 (Hz).

Initial lay-up (°)	Optimal lay-up (°)	Initial generation		Final generation		Relative increase (%)
		Average	Best	Average	Best	Average	Best
[45/−452/45]2s	[90/0/45/−45/0/90/45/−45]s	144.28	161.23	160.80	163.49	11.45	1.40
[0/902/0]2s	[90/0/90/−45/45/90/45/−45]s	135.86	163.97	165.11	167.79	21.53	2.33
[0]8s	[0/90/0/45/−45/45/90/0]s	127.55	137.60	136.33	137.86	6.88	0.19