Free Vibrations of a Trapezoidal Plate with an Internal Line Hinge

Table 2

The first five values of the frequency parameter Ω^∗∗=𝜔/(2𝜋)𝑙²𝜌ℎ/𝐻 for boron-epoxy (𝛽=0) FCFF trapezoidal plates with an internal line hinge located at different positions (tan𝛼₁=1/3, tan𝛼₂=0).

𝑎𝑙	𝑅12	Ω1^∗∗	Ω2^∗∗	Ω3^∗∗	Ω4^∗∗	Ω5^∗∗
		𝑐𝑙=0.5
0	∞	3,7681	14,2391	20,7233	36,8583	50,4389
	Reference [17]	3,7682	14,2395	20,7250	36,8596	50,4602
	1000	3,7592	14,1806	20,5222	36,7239	50,3837
	100	3,6818	13,6411	19,2421	35,7874	49,9690
	10	3,0694	10,3632	17,1129	33,2800	48,3122
	5	2,6281	9,2487	16,8830	32,7645	47,8666
	1	1,4592	7,9784	16,6962	32,2439	47,3974
		𝑐𝑙=0.6
0.2	∞	4,5238	16,0582	24,8369	42,1620	64,6896
	1000	4,5071	16,0437	24,4224	41,7750	64,6747
	100	4,3630	15,9091	21,7174	39,2726	64,5875
	10	3,3755	13,7284	16,9941	34,2600	64,4185
	5	2,7871	12,5570	16,7404	33,4563	64,3882
	1	1,4681	11,2472	16,5925	32,6963	64,3580
		𝑐𝑙=0.7
0.4	∞	7,0576	18,5364	40,1040	53,4753	81,6813
	1000	7,0209	18,5194	39,1366	52,7708	81,2581
	100	6,7104	18,4066	33,2704	48,4565	79,1987
	10	4,8364	18,0067	22,2985	40,7709	76,8733
	5	3,8790	17,7903	20,6121	39,6158	76,6110
	1	1,9656	17,2753	19,3033	38,5349	76,3799