抄録
Up to this time, some characteristic phenomenon about sway of thin circular cylindrical shells had been reported by J. S. M. E. (Genshiro Taishin Sekkeiho Kenkyu Bunkakai). Considering this characteristic phenomenon as nonlinear coupling vibration originated from periodical change (ovalization) of the form of cylinder section and parametric oscillation, we have explained this phenomena theoretically in this report. Here, in analyzing this problem, the new-assumptions was introduced, that there are simultaneously two kinds of mode in the circumferential direction for the former and two kinds of frequency for the latter. Analyzing the sway of cylindrical shell, Galerkins method was used for coupled mode and method of averaging for coupled frequency. In this reports the purpose of considering nonlinearity in strain displacement relation lies not in explanating effects of large amplitude so far thought of, but in the effect of coupling vibration for two mode and two frequency. It has been shown that the analytical result based on the above stated assumption and method coincided well with the experimental observation.
