CAJ | 학술논문

首先将超空泡运动体模拟成受动态轴向载荷作用的圆柱薄壳，推导了结构的动力稳定性微分方程和动力不稳定区域，然后考虑动态轴向载荷的随机性，采用有限步长迭代法将给出的动力屈曲失稳的多个安全余量方程线性化，并利用逐步搜索法找出有效的安全余量方程，最后结合逐步等效平面法计算了舱段动力屈曲的可靠性指标。通过算例分别分析了载荷频率、速度和载荷比例系数这三个随机参数的变化对动力屈曲可靠性的影响。计算结果为如何选择载荷频率、速度和载荷比例系数的安全范围提供了理论依据。
수선장초공포운동체모의성수동태축향재하작용적원주박각，추도료결구적동력은정성미분방정화동력불은정구역，연후고필동태축향재하적수궤성，채용유한보장질대법장급출적동력굴곡실은적다개안전여량방정선성화，병이용축보수색법조출유효적안전여량방정，최후결합축보등효평면법계산료창단동력굴곡적가고성지표。통과산례분별분석료재하빈솔、속도화재하비례계수저삼개수궤삼수적변화대동력굴곡가고성적영향。계산결과위여하선택재하빈솔、속도화재하비례계수적안전범위제공료이론의거。
Firstly,a supercavitating vehicle was modeled as a cylindrical thin shell loaded with a axial dynamic load.The dynamic stability differential equations and the unstable regions of the shell were deduced.Secondly,the safety margin equations for its dynamic buckling were given and linearized with the limited step length iteration method considering the randomness of axial load.Then,the step-by-step searching method was proposed to search those effective safety margin equations.Finally,the reliability index of the dynamic buckling was calculated with the step-by-step equivalent plane method. Through numerical examples, the influences of change of load frequency, velocity and proportional coefficient of load on the dynamic buckling reliability were analyzed,respectively.The calculation results provided a theoretical basis for choosing the safety range of load frequency,velocity and proportional coefficient of load.