Model Updating of a Stitched Sandwich Panel Based on Multistage Parameter Selection

Table 8

Comparison of modal frequencies between test and numerical models of cases 1 and 2.

Mode order	Test (Hz)	Numerical mode
		Initial (Hz)	Error (%)	Case 1		Case 2
				Updated (Hz)	Error (%)	Updated (Hz)	Error (%)
1	189.90	213.32	12.33	187.29	−1.37	189.16	−0.39
2	204.59	125.37	−38.72	201.34	−1.59	201.17	−1.67
3	387.64	415.25	7.12	380.19	−1.92	378.37	−2.39
4	439.56	324.71	−26.13	441.70	0.49	447.81	1.88
5	583.81	610.97	4.65	587.73	0.67	584.30	0.08
6	672.74	561.10	−16.59	655.02	−2.63	670.85	−0.28
7	751.18	768.72	2.33	767.95	2.23	763.80	1.68
8	790.16	817.67	3.48	803.54	1.69	805.00	1.88
9	878.64	875.59	−0.35	912.01	3.80	893.22	1.66
10	916.01	994.60	8.58	937.48	2.34	961.01	4.91
Mean error			12.03		1.87		1.68