Vibration Characteristics of Ring-Stiffened Functionally Graded Circular Cylindrical Shells

Table 12

Variation of natural frequencies against circumferential wave number 𝑛, type II 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	14.018	14.071	14.130	14.245	14.362	14.436	14.458
2	35.176	33.434	33.995	34.126	34.274	34.553	34.839	35.043	35.105
3	95.883	91.090	92.651	93.015	93.421	94.188	94.972	95.519	95.691
4	182.65	173.50	176.49	177.18	177.96	179.42	180.91	181.95	182.28
5	294.72	279.96	284.78	285.90	287.15	289.51	291.92	293.60	294.13
6	431.95	410.31	417.37	419.02	420.85	424.31	427.85	430.31	431.08
7	594.24	564.47	574.19	576.45	578.98	583.74	588.60	591.98	593.05
8	781.54	742.40	755.17	758.14	761.47	767.73	774.12	778.57	779.97
9	993.81	944.04	960.28	964.06	968.29	976.24	984.38	990.03	991.81
10	1231.0	1169.4	1189.5	1194.2	1199.4	1209.3	1219.3	1226.3	1228.5