The Modeling Method for Vibration Characteristics Analysis of Composite-Laminated Rotationally Stiffened Plate

Table 6

The first eight-order frequency parameter Ω of rotationally isotropic stiffened plates under different boundary conditions.

Boundary condition	Method	Modal order
		1	2	3	4	5	6	7	8
		Stiffened annular sector plate: , ϑ = 120°
CFCF	Present method	0.802	1.373	2.750	4.299	4.935	5.893	7.603	10.383
	FEM	0.759	1.421	2.961	4.194	5.067	6.118	7.614	10.098
CCCC	Present method	5.772	9.749	14.273	14.829	17.379	19.576	23.227	24.210
	FEM	5.659	9.996	13.391	15.117	17.383	19.761	23.439	25.070
		Stiffened circular sector plate: , ϑ = 120°
CFC	Present method	2.532	5.613	7.666	9.431	11.538	12.499	14.468	16.949
	FEM	2.720	5.396	7.747	9.472	11.828	13.129	14.106	17.020
CCC	Present method	5.456	9.206	11.850	12.558	16.391	17.845	18.342	20.828
	FEM	5.343	9.129	11.096	12.711	16.457	17.843	18.249	21.000
		Stiffened annular plate: , ϑ = 360°
CF	Present method	0.735	0.735	0.915	0.926	0.926	1.747	1.748	3.194
	FEM	0.744	0.744	0.906	0.931	0.931	1.883	1.883	3.078
CC	Present method	4.280	4.655	4.655	5.404	5.404	7.572	7.583	10.479
	FEM	4.397	4.618	4.619	5.589	5.589	7.688	7.689	10.744
		Stiffened circular plate: , ϑ = 360°
F	Present method	0.802	0.802	1.307	1.599	1.605	2.635	2.635	2.762
	FEM	0.780	0.780	1.443	1.678	1.679	2.633	2.633	2.756
C	Present method	1.404	2.514	2.515	4.387	4.387	4.780	7.008	7.018
	FEM	1.430	2.661	2.661	4.644	4.645	4.857	7.252	7.253