Vibration Characteristics of Ring-Stiffened Functionally Graded Circular Cylindrical Shells

Table 6

Variation of natural frequencies against circumferential wave number n, type I FG cylindrical shell with nickel 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	14.715	14.025	14.436	14.421	14.360	14.246	14.134	14.066	14.046
2	35.517	33.764	34.836	34.768	34.618	34.342	34.068	33.885	33.828
3	96.256	91.453	94.364	94.184	93.772	93.017	92.275	91.782	91.626
4	183.17	174.01	179.56	179.21	178.43	176.99	175.57	174.64	174.34
5	295.50	280.72	289.66	289.11	287.84	285.52	283.24	281.73	281.25
6	433.06	411.40	424.51	423.70	421.84	418.44	415.10	412.88	412.18
7	595.76	565.96	584.00	582.89	580.33	575.65	571.05	568.00	567.04
8	783.53	744.35	768.06	766.60	763.24	757.08	751.04	747.03	745.76
9	996.33	946.51	976.66	974.80	970.53	962.70	955.02	949.92	948.31
10	1234.1	1172.4	1209.7	1207.46	1202.17	1192.5	1182.9	1176.6	1174.6