Analysis and Manufacturing of Ultra Thick Laminates for Future Aircraft Applications
2008 (English)In: ECCM-13, 2008, 2008Conference paper (Other academic)
Compact and highly loaded composite components experience extensive transverse shear stress concentrations in areas of load introduction and curved sections. Standard 3D multilayered composite brick elements are employed to analyze UTL. For the purpose of validation several full-scale test components with T-cross section have been manufactured with thicknesses ranging from 60-90mm. In a first approach single non interactive failure criteria have been used due to the uncertainty of out of plane material properties. Despite the fact that the used element type provides a simple mean of modeling and analyzing UTL, it is found that the element formulation strictly limits the accuracy of transverse shear stress prediction. The quadratic or even linear approximation of in plane displacements does not account for the irregular distribution in thickness direction . Global deformations of the geometry can however be calculated with good results. Most failure modes experienced, are found to be dominated by transverse shear or out of plane peeling stresses. Particularly in the region of load introduction. For the analysis of the final landing gear fitting material restricted correction factors are introduced. In addition to the T-Sections, large so called ‘Double Corners’ are tested in both in plane and out of plane direction to develop effective countermeasures for premature failure modes, such as throat washers and load distribution plates. The utilized modified VAP cycle has significant benefits compared to closed mould processes, such as reduced tooling costs and high flexibility. For curved UTL sections spring back effects and preform compression rates are considered to improve laminate quality.
Place, publisher, year, edition, pages
Ultra thick laminates, open mould manufacturing, vacuum assisted process, multilayered composite brick element
IdentifiersURN: urn:nbn:se:kth:diva-47651OAI: oai:DiVA.org:kth-47651DiVA: diva2:455895
European Conference on Composite Materials ECCM-13, Stockholm, Sweden, 2008
QC 201111112011-11-112011-11-112015-08-28Bibliographically approved