A Hybrid Finite Element-Fourier Spectral Method for Vibration Analysis of Structures with Elastic Boundary Conditions

Table 5

Comparison of the first ten natural frequencies of the rectangular-half circular plate.

Mode order	FEA^a	Hybrid^b	Difference
	DOF = 2472	DOF = 781	—
1	0.8266	0.8265	0.01%
2	0.8309	0.8311	−0.02%
3	1.876	1.876	0.00%
4	1.9316	1.9308	0.04%
5	2.1311	2.1299	0.06%
6	2.8449	2.8444	0.02%
7	3.5087	3.5053	0.10%
8	3.9185	3.9167	0.05%
9	4.7067	4.7043	0.05%
10	4.9564	4.9553	0.02%

Note: FEA results are calculated by using ANSYS with 773 elements.
^bResults with = = 12 at the FSM zone and 22 elements at the edge of the coupled line and the element matrix of the semicircular plate were derived from the ANSYS software.