Structure Design And Analysis Of Pressure Hull In Manned Submersible

With the development of economy and industry, land resources can not meet the needsof the rapid development of the society. The ocean, accounting for70.8%of the Earth’ssurface, contains abundant oil, gas, and mineral resources, it is the tomorrow of human beingsand the hope of future. The deep-water resources exploration and exploitation turns into thenew central issue of the ocean development. The HOV, which serves as a tool of thedeep-water scientific investigation and exploitation, can bring the scientists into the deep seafor direct scientific investigation and research, and is irreplaceable in the areas of deep-watergeological research, resources investigation and ocean biological research. The pressure hullstructure is the most important aspect of the HOV technology, and affects the security of thesubmersible, human and equipments. Therefore, the strength and stability of the pressure hullstructure must be good enough.Based on the National Science and Technology Major Project “Study on Concept Designof Deep Water Light Work Operation HOV”, the pressure hull structure design，the strengthanalysis and the stability analysis are carried out.Firstly, the pressure hull materials, the structure types, the safety factor and the innerdiameter of the spherical shell are determined according to the factors considered in thepressure hull design and the best design process. The thickness of the pressure hull iscalculated according to CCS rules, as well as the weight and displacement of the pressure hull,based on the hull’s preliminary design size. Secondly, the advantages and disadvantagesbetween the linear buckling and the nonlinear buckling in the stability analysis are compared,and the nonlinear buckling method are chosen to analyze the stability of the pressure hull. Thecalculation results according to CCS rules, GL rules, the empirical formulas and FEM methodare compared, which proves that the analysis results of FEM method are satisfying accordingto the buckling calculation results of the rules. Then, the impact of initial imperfection onpressure hull stability is discussed. The critical buckling pressure is promoted by theimprovement of personal accessing cabin fence and the main and side observation windowparameters. At last, models of the pressure hull with openings and no openings are established.The strength of the pressure hull structure is analyzed. According to CCS rules, the strengthof the whole structure and local areas around openings is satisfying. A kind of “beveledtransition” for strengthening is proposed, which is quite different from traditional trunk bulkhead way. The stress distribution of this kind of strengthening structure is more even, andthe stress focusing situation is effectively decreased.