Finite element analysis of additive manufacturing-enabled cellular architectures for morphing airfoil applications en en Morphing airfoil structures require internal architectures that provide both sufficient flexibility and structural reliability while remaining compatible with advanced manufacturing techniques. In this study, the structural performance of different cellular core configurations suitable for additive manufacturing was investigated using finite element analysis. Four internal architectures were considered, including a conventional honeycomb structure (HC), a re-entrant auxetic structure (RA), and two modified auxetic configurations (CA-1 and CA-2). The airfoil models were subjected to loading conditions ranging from 50 N to 300 N to evaluate stress distribution and deformation behavior. The results demonstrate that cellular geometry significantly influences the mechanical response of the morphing airfoil. The HC configuration exhibited the highest stiffness, with the lowest displacement (2.63 mm at 300 N), but showed pronounced stress concentration. In contrast, the auxetic configurations provided more uniform stress distribution due to their geometry-driven deformation mechanisms. The CA-2 design showed the highest deformation capability, indicating enhanced flexibility and morphing potential, while also maintaining a relatively uniform stress distribution. In contrast, the RA configuration exhibited localized stress concentration associated with its re-entrant geometry. Overall, the modified auxetic configuration CA-2 demonstrated the most balanced mechanical performance by combining improved stress redistribution with high deformation capability. The results highlight that geometrically optimized auxetic structures, which can be readily fabricated using laser-based additive manufacturing techniques, offer significant potential for morphing airfoil applications. 41 48 Tyou Al-Oussainne Department of Aeronautical Engineering, Faculty of Aviation and Space Sciences University of Kyrenia, Kyrenia, Mersin 10 Turkey Ata Khabaz-Aghdam Department of Aeronautical Engineering, Faculty of Aviation and Space Sciences University of Kyrenia, Kyrenia, Mersin 10 Turkey ata.khabazaghdam@kyrenia.edu.tr Morphing airfoil Cellular internal structures Auxetic structure Finite element analysis Vol 6 No 1 Paper 5.pdf [1] S. Barbarino, O. Bilgen, R.M. Ajaj, M.I. Friswell, D.J. Inman, A Review of Morphing Aircraft, J. Intell. Mater. Syst. Struct. 22 (2011) 823–877. https://doi.org/10.1177/1045389X11414084. ##[2] J. Valasek, Morphing aerospace vehicles and structures, American Institute of Aeronautics and Astronautics. 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