超空泡航行体双层壳结构动力稳定性分析

Dynamic Stability Analysis of Supercavitating Double Shells

针对超空泡航行体轴向受力特点,建立超空泡航行体双层壳结构有限元模型,对结构动力稳定性进行分析。数值计算表明,当壳间实肋板厚度增大或环向肋骨数量和尺寸增加时,动力失稳区域整体下移,不稳定激发频率下降,失稳区域宽度减小幅度较小;当壳间间距减小或纵向肋骨数量和尺寸增加时,双层壳结构动力不稳定激发频率上升,动力失稳区域宽度较大幅度减小,动力不稳定激发程度显著降低。

A finite dement model for supercavitafing underwater vehicles was developed and the dynamic stability of supercavitafing double shells was investigated to obtain the instability maps for varying vehicle＇s velocity considering the time-dependent properties of the longitudinal loads. The computational results indicate that with the increment of the thickness of the annular plates linking between inner and outer shells or the number and dimension of the circumferential stiffeners, the frequencies corresponding to dynamic instability decline and the extension of the regions of dynamic instability is reduced lightly, while the frequeneies corresponding to dynamic instability ascend and the dynamic stability is enhanced remarkably with the spae between inner and outer shells decreased or the number and dimension of the longitudinal stiffeners increased.