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

Table 5

Frequency parameter Ω of stiffened composite annular sector plate and stiffened composite annular plate with different numbers and sizes of stiffeners.

Number of stiffeners n	Modal order
	1	2	3	4	5	6	7	8
	,
	Stiffened annular sector plate; ϑ = 180°, CCCC
n = 0	5.124	5.129	5.240	5.569	6.217	7.245	8.601	10.287
n = 1	3.489	6.704	9.949	13.155	13.443	15.967	16.248	18.928
n = 2	3.618	6.943	7.080	9.327	10.269	10.968	12.201	13.530
n = 3	3.541	5.758	6.706	8.076	8.263	9.706	9.845	9.997
	Stiffened annular plate: ϑ = 360°, CC
n = 0	5.101	5.101	5.124	5.124	5.135	5.138	5.138	5.339
n = 1	1.094	3.467	3.467	6.659	6.659	9.880	9.880	12.432
n = 2	1.118	3.603	3.603	6.155	6.913	6.913	7.073	7.073
n = 3	1.201	3.528	3.528	4.644	5.749	5.749	6.680	6.680
	,
	Stiffened annular sector plate: ϑ = 180°, CCCC
n = 0	5.124	5.129	5.240	5.569	6.217	7.245	8.601	10.287
n = 1	2.806	4.961	7.239	9.548	11.857	14.154	16.403	18.061
n = 2	2.898	5.166	7.543	8.189	9.262	9.941	10.820	12.318
n = 3	2.900	5.067	6.209	7.343	7.519	9.317	9.629	10.076
	Stiffened annular plate: ϑ = 360°, CC
n = 0	5.101	5.101	5.124	5.124	5.135	5.138	5.138	5.339
n = 1	1.513	2.778	2.778	4.895	4.895	7.137	7.137	9.405
n = 2	1.511	2.871	2.871	5.104	5.104	7.451	7.451	7.800
n = 3	1.616	2.876	2.876	5.011	5.011	5.709	6.197	6.197