Burst Pressure Study And Design Optimization For Filament Wound Composite Pressure Vessels

Filament-wound composite pressure vessels are widely used in aerospace,vehiclemounted hydrogen storage cylinders and other emerging development fields due to their high specific strength,high specific stiffness,light weight,long service life and low cost.In recent years,there have been many researches on the fiber-winding process,lightweight design and load-bearing strength of composite pressure vessels.However,the failure mode of filamentwound composite pressure vessel is very complex and there are many influencing factors.At present,there are many researches on the mechanical properties of filament-wound layer,but there are few studies on the overall structural mechanical properties of pressure vessel,mostly considering the thickness and winding angle of filament-wound layer and ignoring the influence of lay-up sequences.In view of the above problems,the overall structure design of filament-wound composite pressure vessel is carried out in this paper.The burst pressure and failure mechanism of filament-wound composite pressure vessel are studied by hydraulic blasting test and finite element numerical simulation considering damage evolution of composite material.On this basis,the filament-wound composite pressure vessel is structural optimized.Specific research work includes: design of aluminium alloy liner structure is completed according to design conditions and specifications of aluminium alloy liner filament wound composite pressure vessel.According to the grid theory and the classical laminate theory,the preliminary winding angle and winding thickness of the filament winding layer are designed.The burst pressure of aluminium alloy liner filament wound composite pressure vessel was obtained by hydraulic blasting test.A 2-dimensional axisymmetric composite pressure vessel finite element model was established by using WCM plug-in in the finite element analysis software ABAQUS to simulate the blasting test.Fine modeling of filament winding layer is completed in the model.User UMAT subprogram based on Hashin failure criterion is introduced to simulate progressive damage characteristics of composites during pressurization.The value and position of blasting pressure are predicted by progressive damage analysis.It is found that the blasting pressure and position simulated by finite element agree well with the test results.On this basis,the stress of each part of filament-wound composite pressure vessel under different internal pressures is analyzed.In order to make the bearing capacity of the filament-wound composite pressure vessel meet the design requirements and burst in safety mode according to the specifications,optimum schemes for the structure of the filamentwound composite pressure vessel were put forward by means of hole enlargement process and adjustment of the filament lay-ups,and the finite element verification was carried out.In this paper,the burst pressure and mechanical properties of filament-wound composite pressure vessel are studied by combining theory,experiment and finite element simulation.A closed-loop design strategy for filament-wound composite pressure vessel was put forward,which is based on theoretical design-test combined with finite element verification-structure optimization.Good results were obtained.It provides a new idea for structure design and optimization of filament-wound composite pressure vessel and has a good guiding effect on production practice.