For simplifying the analysis of stiffening cylindrical shell in rocket, the computational method of torsional rigidity in the area-equivalence method was studied for the stringers in stiffening cylindrical shell, it is shown that the effect of stringers on the torsional rigidity of stiffening cylindrical shell is negligible. The equivalent beam or shell model with uniform thickness, the equivalent shell model with varied thickness and three dimensional (3-D) beam-shell model were proposed to solve the inherent torsional vibration frequency, and the features of these models were discussed. It was theoretically revealed that the obtained equivalent thickness by the area-equivalence method could not be directly used to calculate the torsional rigidity. Two modification methods, namely, the rigidity reduction method and frequency modified method, were presented when the equivalent thickness was directly utilized to solve the torsional frequencies. Numerical comparisons validate the proposed methods and models.
����,������,������,��.�������ػ������ѧ�ؼ����������չ����[J].�����뺽�����ؼ���,2000(1):29-37 Wang Yi,Zhu Liwen, Wang Mingyu,et al.Summary of some key technologies on dynamics of large launch vehicle[J].Missiles and Space Vehicles,2000(1):29-37 (in Chinese)
������,�ŵ���.����ṹ����Ԫ��������������[J].ǿ���뻷��,1988(3):45-53 Wang Longsheng,Zhang Dewen.Several problems in structural finite element analysis of rockets[J].Structure & Environment Engineering,1988(3):45-53 (in Chinese)
���ֺ�.�������:�ϲ�[M].����:�������,1989:469-475 Long Lehao.Systems design:volume I[M].Beijing:Astronautics Press,1989:469-475 (in Chinese)
������.���ػ������ѧ��ģ������б��Ԥʾ����[J].�й���ѧ,E��:������ѧ,2009,39(3):469-473 Pan Zhongwen.The Dynamical modelling and modal slope indicate technique of launch vehicle [J].Science in China,Series E:Technological Sciences[J],2009,39(3):469-473 (in Chinese)
�����,����,���.ǣ���ͷŹ����л��Һ���ƽ����Ľ�ģ�о�[J].ǿ���뻷��,2008,35(6):14-18 Li Daokui,Liu lin,Wan Jun.Study of the model of rocket-s liquid propellant in the process of hold-down and release[J].Structure & Environment Engineering,2008,35(6):14-18 (in Chinese)
������,�ٿ���.������ȫ������ѧ�����о�[J].�ѧ��,2009,30(3):821-826 Wang Jianmin,Rong Kelin.The research of dynamic characteristics for the strap-on launch vehicle[J].Journal of Astronautics,2009,30(3):821-826(in Chinese)
Yoshiki Morino.Vibration test of 1/5 H-II launch vehicle .AIAA-87-0783,1987