Elastocaloric cooling technology represents a promising alternative to conventional vapour-compression technology. Because of fatigue resistance and favourable heat transfer, elastocaloric regenerator prototypes often use thin-walled cylindrical shell made up of shape memory alloys. The prominent nonlinear behaviour can in combination with thin-walled geometry cause global and local instabilities under compressive loading. To determine a stable area of geometries we developed a numerical model in the finite element method program Abaqus 2021 using shell elements and the built-in material model which is based on Auricchio's formulation. Geometric and material parameter were determined based on existing experimental analyses, which we used to verify the obtained results. For the onset of instabilities, we used a combination of a perturbation force and the random perturbation of the mesh. Using the presented model, we performed buckling analyses for a wider set of geometries and summarized the obtained results in the form of a buckling mode phase diagram in which we determined an area of stabile geometries and individual buckling modes. With the performed analyses we showed that the presented model can yield results which are comparable with those of existing numerical and experimental analyses.
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