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- Olsson, Robin, 1958, et al.
(författare)
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Design, Manufacture, and Cryogenic Testing of a Linerless Composite Tank for Liquid Hydrogen
- 2024
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Ingår i: Applied Composite Materials. - : Springer Nature. - 1573-4897 .- 0929-189X. ; 31:4, s. 1131-1154
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Tidskriftsartikel (refereegranskat)abstract
- This paper describes design, manufacture, and testing of a linerless composite vessel for liquid hydrogen, having 0.3 m diameter and 0.9 m length. The vessel consists of a composite cylinder manufactured by wet filament winding of thin-ply composite bands, bonded to titanium end caps produced by additive manufacturing. The aim was to demonstrate the linerless design concept with a thin-ply composite for the cylinder. The investigation is limited to the internal pressure vessel, while real cryogenic tanks also involve an outer vessel containing vacuum for thermal insulation. Thermal stresses dominate during normal operation (4 bar) and the layup was selected for equal hoop strains in the composite cylinder and end caps during filling with liquid hydrogen. Two vessels were tested in 20 cycles, by filling and emptying with liquid nitrogen to 4 bar, without signs of damage or leakage. Subsequently, one vessel was tested until burst at almost 30 bar.
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| 2. |
- Singh, Vivekendra, 1987, et al.
(författare)
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Rate dependent compressive failure and delamination growth in multidirectional composite laminates
- 2024
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Ingår i: Journal of Composite Materials. - : SAGE Publications Ltd. - 1530-793X .- 0021-9983. ; 58:3, s. 419-431
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Forskningsöversikt (refereegranskat)abstract
- A novel intralaminar model has, for the first time, been applied and validated for the rate-dependent failure of multidirectional carbon/epoxy laminates. Quasi-static compressive failure is evaluated by the growth of intralaminar ratedependent damage combined with the interaction of cohesive zones for interlaminar delamination. A special feature of the intralaminar model is the homogenised ply response, allowing simultaneous damage-degradation of the polymer matrix combined with the fibres. To model the observed quasi-brittle failure response of the plies under finite deformation, we have used a viscoelastic-viscoplastic matrix combined with damage and isotropic hardening behaviour. Elastic transverse isotropy is used to model the fibre reinforcement of the plies. Standard cohesive surfaces are used to model the initiation and propagation of delamination. Numerical simulations using ABAQUS/Explicit are performed to predict the growth and delamination of intralaminar damage under compression in different laminates with 56 plies of IM7/8552 carbon/epoxy. Predictions of stress versus strain and damage growth are shown to agree well with experimental results for a range of strain rates and stacking sequences.
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