【作者】 唐飞；

【导师】 孙家斌；

【作者基本信息】 大连理工大学 ， 工程力学， 2019， 硕士

【摘要】 深潜器的耐压壳起着抵御深海水压,庇护深潜器内部操纵人员和机械器具安全的重要功能。本文考虑了生物界蛋壳的优良特性,研究了一种蛋形耐压壳体,采取现有的蛋壳数学模型,建立蛋形耐压壳模型,对蛋壳形状、蛋壳厚度、壳体内部加筋体结构、壳体材料以及壳上开孔等因素对壳体稳定性的影响进行了分析。主要内容与结论如下:（1）解析蛋形耐压壳数学参数,给出蛋形曲线图和方程,推导蛋形壳经向曲率半径、纬向曲率半径、蛋形系数、体积公式等运算方式,并给出蛋形耐压壳的线弹性理论解公式;结合耐压壳的设计因素和耐压壳稳定性失效与四种等体积常规壳型进行对比,蛋形耐压壳的各项功用均较好,验证了蛋形耐压壳的设计可行性。（2）对金属（各项同性）材料蛋形耐压壳体进行特征值屈曲（线性）分析,参照常用球壳的体积（直径为2m）,建立金属蛋壳模型,在不同壳体厚度下,蛋形耐压壳体的屈曲临界载荷的模拟值与理论解相差在15%以内,屈曲位置发生在蛋形耐压壳体的腰部,理论值偏大;接着分析了在壳体内部加筋的影响,结果表明加筋能够有效提高壳体稳定性,且相比于加纵向筋,环向筋的加载对稳定性能提高更显著,网格加强筋对壳体稳定性的增强效果最好;通过正交试验分析壳体厚度对蛋形耐压壳体的稳定性影响最大;其次是加筋方式,加环筋方式要比加纵筋方式影响大,但总体影响效果优于加筋体厚度;对稳定性影响最差的是加筋体厚度。（3）对复合材料含损伤蛋壳非线性屈曲进行了分析。提出动力显式结合Hashin损伤失效准则的模拟方法,分析了不同蛋形系数下的壳体屈曲性能,结果表明蛋形结构不能过于细长,也不能过于矮胖,蛋形系数取0.7到0.8之间较好,蛋形结构的腰部承压要优于底部承压;通过考虑材料损伤与否的对比,屈曲后具有材料损伤的壳体的位移载荷曲线更低,屈曲状态也有所区别,而其临界屈曲载荷差距无几;通过分析复合材料的分布方式对壳体稳定性影响,Gpl-epo和Fib-gpl-epo材料的X型分布优于O型分布优于A型分布优于V型分布,且随着壳体层数、最高层强度的增大越明显;不同的碳纤维铺层方向也有影响,[0/90]_10S的碳纤维铺层方式屈曲性能最好,[90/0]_10S的碳纤维铺层方式屈曲性能次之,[45/-45]_10S的碳纤维铺层方式屈曲性能最差;对壳体头部开孔（单孔）、头部底部开孔（双孔）,以及开孔半径对壳体稳定性进行了分析,开孔会降低稳定性,半径越大降低越多,开孔半径达到200mm时,单孔减小了9.34%,双孔减小了14.47%,且通过减小蛋形系数,为0.7时,双孔的屈曲位置会由壳体底部转移到腰部。更多还原

【Abstract】 The pressure shell of deep submersible plays an important role in resisting the deep water pressure and protecting the safety of personnel and equipment inside the submersible.In this paper,considering the excellent characteristics of biological eggshell,a kind of egg-shaped pressure-resistant shell was studied,and the existing egg-shaped mathematical model was adopted to establish the egg-shaped pressure-resistant shell model.The main contents and conclusions are as follows:(1)The mathematical model of the egg-shaped pressure-resistant shell is analyzed,the curve diagram and equation of the egg-shaped shell are given,the calculation methods of the first curvature radius,the second curvature radius,the coefficient of the egg-shaped shell and the volume formula are derived,and the solution formula of the linear elasticity theory of the egg-shaped pressure-resistant shell is given.In combination with the design factors of the pressure shell and the failure of the stability of the pressure shell,the performance of the eggshaped pressure shell is better than that of the conventional shell of the same volume,which verifies the feasibility of the design of the egg-shaped pressure shell.(2)Egg-shaped pressure-tight shell of metal material(isotropic material)eigenvalue buckling analysis,with reference to the volume of a spherical shell is commonly used(diameter of 2 m),metal shell model is established,under the different shell thickness,egg-shaped pressure-tight shell buckling critical load of the simulated values within 15%,the difference between the theoretical solution is buckling occurred in egg-shaped pressure shell of the waist,the theoretical value is larger.The results show that the reinforcement can effectively improve the stability of the shell.Compared with the longitudinal reinforcement,the cyclic reinforcement has more significant effect on the stability of the shell,and the grid reinforcement has the best effect on the stability of the shell.The effect of shell thickness on the stability of egg-shaped pressure-resistant shell is analyzed by orthogonal test.The second one is the stiffening method.The ring-stiffening method has a greater effect than the longitudinal one,but the overall effect is better than the thickness of the stiffening body.The worst effect on stability is the thickness of the reinforcement.(3)The nonlinear buckling of composite eggshell with damage was analyzed.The simulation method of dynamic explicit combined with Hashin damage failure criterion was proposed,and the shell buckling performance under different egg-shaped coefficients was analyzed.The results showed that the egg-shaped structure could not be too long and thin,nor too short and fat.By considering the comparison of material damage or not,the displacement load curve of shell with material damage after buckling is lower,and the buckling state is also different,but the critical buckling load has little difference.By analyzing the influence of distribution mode of composite materials on shell stability,the x-type distribution of gpl-epo and fib-gpl-epo materials is better than the o-type distribution,better than the a-type distribution and better than the v-type distribution.Different carbon fiber lamination directions also have an impact.The [0/90]10S carbon fiber lamination mode has the best buckling performance,followed by [90/0]10S carbon fiber lamination mode,and [45/45]10S carbon fiber lamination mode has the worst buckling performance.Head to shell opening hole at the bottom of the(single),head(double holes),stability and hole radius on the shell was analyzed,and the hole will reduce the stability,the larger the radius decrease,the more open hole radius of 200 mm,puckering reduced 9.34%,double holes decrease by 14.47%,and by reducing,egg-shaped coefficient of 0.7,double holes of flexion position from the bottom of the shell is transferred to the waist.更多还原