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Abstract: The stress distributions in metal/adhesive/foam planar joints subjected to biaxial tensile load and thermal load was investigated through a semi-analytical model. The shear deformation of adherends was accounted for according to a linear law in order to obtain closed-form solutions. For the model validation, a comparative study with a finite element (FE) simulation was carried out. A 2D behavior of stress fields is observed due especially to the Poisson''s ratio effects and the biaxial nature of loads. The through thickness shear stresses are comparable to normal stresses; therefore, the adherend shear deformation must be accounted for correct failure prediction. According to the comparison with FE results, the normal stress distributions at any location in the foam and the shear stresses in the foam regions close to the adhesive surface can be well predicted by the proposed model. The through thickness shear stresses, however, showed to vary according to a cubic law rather than a linear law. [Copyright &y& Elsevier]

Abstract: The paper presents a semi-analytical model aiming to study the thermomechanical behavior of the insulation/metallic shell assembly of cryogenic reservoirs during the fueling step. The proposed model is applied to explore the influences of material properties and insulation dimensions on the stress distributions, and the ranges of applicability of the classical design formula. The present parametric study shows that the Poisson’s ratio strains have significant effects on stress fields in the insulation. The through-thickness shear deformation in the insulation must be taken into account for avoiding erroneous failure prediction. The maximum normal and shear stresses occur respectively at the center and close to free borders of the insulating panel. The failure of the assembly will occur in the insulating foam component or at least at the foam/adhesive interface due to the higher stiffness and strength of cryogenic adhesive layer than the foam. In addition, the adhesive layer can be neglected in the modeling by assuming the insulation putted in direct contact with the metallic shell. The applicability ranges of classical simple formula often used to dimension reservoir insulation are summarized in . When one of these conditions is not fulfilled, the proposed semi-analytical or more complex approaches should be used. [Copyright &y& Elsevier]