Vibration Characteristics of Ring-Stiffened Functionally Graded Circular Cylindrical Shells

Table 10

Variation of natural frequencies against circumferential wave number 𝑛, type I FG cylindrical shell with stainless steel ring stiffeners (𝑚=1, ℎ/𝑅=0.05, 𝐿/𝑅=20, 𝑑/𝑏=1.334).

𝑛	𝑁^𝑆𝑆=0	𝑁^𝑁=0	𝑁=0.5	𝑁=0.7	𝑁=1	𝑁=2	𝑁=5	𝑁=15	𝑁=30
1	14.482	13.800	14.206	14.192	14.131	14.019	13.908	13.841	13.821
2	35.176	33.434	34.499	34.433	34.283	34.009	33.737	33.555	33.498
3	95.883	91.090	93.995	93.817	93.405	92.652	91.911	91.419	91.263
4	182.65	173.50	179.04	178.70	177.91	176.48	175.07	174.13	173.83
5	294.72	279.96	288.89	288.35	287.08	284.76	282.48	280.97	280.49
6	431.95	410.31	423.41	422.60	420.75	417.35	414.01	411.79	411.09
7	594.24	564.47	582.49	581.38	578.83	574.15	569.56	566.51	565.55
8	781.54	742.40	766.08	764.63	761.27	755.12	749.08	745.07	743.81
9	993.81	944.04	974.15	972.31	968.04	960.22	952.54	947.45	945.84
10	1231.0	1169.4	1206.6	1204.4	1199.1	1189.4	1179.9	1173.6	1171.6