Analysis of Implosion Protection Effect of Ceramic and Titanium Alloy Hollow Spheres Wound With Carbon Fiber

As an important part of deep-sea submersibles, once a catastrophic implosion occurs, the pressure-resistant structure will pose a huge threat to the vitality of deep-sea equipment. Therefore, it is necessary to conduct relevant research on implosion protection. In this work, we selected ceramic and titanium alloy hollow spheres as deep-sea flotation devices, and formed a composite pressure-resistant structure with both lightweight and implosion protection advantages by winding carbon fiber outside them. Based on the open-source solver OpenRadioss, the arbitrary Lagrangian-Eulerian method is used to simulate the implosion process of composite hollow spheres. Firstly, the feasibility of the numerical method is verified by comparing with the relevant experiment. Secondly, the response analysis of the two composite hollow spheres is carried out. The 3D Hashin criterion, the maximum principal stress criterion and the Johnson-Cook failure criterion are used to describe the failure of carbon fiber reinforced polymer (CFRP), ceramic and titanium alloy respectively. By comparing the flow field response and structural collapse form, the influence of outer winding carbon fiber on the implosion characteristics of ceramic brittle material hollow spheres and titanium alloy ductile material hollow spheres is discussed. The failure modes of hollow spheres with different lining materials are summarized, and the advantages of this scheme in lightweight and implosion protection are highlighted. In summary, this work not only clarifies the mechanism of implosion, analyzes the structural response, and proposes implosion protection measures, but also provides a reference for the material selection and design of deep-sea equipment structures.