Hygrothermal Stability analysis of bio-inspired Meta-Nanocomposite Shells (ISAV2025)
پذیرفته شده برای ارائه شفاهی
کد مقاله : 1137-ISAV2025 (R1)
نویسندگان
1عضو هیئت علمی دانشگاه بین المللی امام خمینی(ره)
2دانشجوی دانشگاه آزاد اسلامی واحد علوم و تحقیقات تهران
3عضو هیئت علمی دانشگاه آزاد اسلامی واحد علوم و تحقیقات
چکیده
The present study investigates the effectiveness of a bio-inspired auxetic lattice metamaterial core in enhancing the hygrothermal–torsional stability of carbon nanotube (CNT)-reinforced sand-wich cylindrical shells. The shells are subjected to various hygrothermal conditions, including uni-form, linear, and nonlinear temperature and moisture gradients. CNTs are embedded within a tem-perature- and moisture-dependent polymer matrix in the face sheets. The proposed bio-inspired aux-etic core, inspired by butterfly wing patterns, exhibits superior adaptability, stiffness, and stability due to its negative Poisson’s ratio (NPR), showing improved performance compared to conventional re-entrant type. The equilibrium equations are derived using nonlinear Donnell shell theory with von Kármán geometric nonlinearity and solved via the Galerkin method to obtain buckling and post-buckling responses. The model’s accuracy is verified against previous studies. The findings reveal that the butterfly-shaped core achieves up to 23.33% higher stability than the conventional re-entrant core, underscoring its potential for lightweight, high-performance auxetic shell structures. Furthermore, an in-depth parametric analysis is conducted to examine the influence of the hygro-thermal environment on the shell’s stability behavior.
کلیدواژه ها
Keywords: bio-inspired auxetic core؛ carbon nanotube-reinforced composite؛ hygrothermal–torsional stability؛ nonlinear buckling
Title
Hygrothermal Stability analysis of bio-inspired Meta-Nanocomposite Shells (ISAV2025)
Authors
Farzad Ebrahimi, Mohammadhossein Goudarzfallahi, Ali َAlinia-ziazi
Abstract
The present study investigates the effectiveness of a bio-inspired auxetic lattice metamaterial core in enhancing the hygrothermal–torsional stability of carbon nanotube (CNT)-reinforced sand-wich cylindrical shells. The shells are subjected to various hygrothermal conditions, including uni-form, linear, and nonlinear temperature and moisture gradients. CNTs are embedded within a tem-perature- and moisture-dependent polymer matrix in the face sheets. The proposed bio-inspired aux-etic core, inspired by butterfly wing patterns, exhibits superior adaptability, stiffness, and stability due to its negative Poisson’s ratio (NPR), showing improved performance compared to conventional re-entrant type. The equilibrium equations are derived using nonlinear Donnell shell theory with von Kármán geometric nonlinearity and solved via the Galerkin method to obtain buckling and post-buckling responses. The model’s accuracy is verified against previous studies. The findings reveal that the butterfly-shaped core achieves up to 23.33% higher stability than the conventional re-entrant core, underscoring its potential for lightweight, high-performance auxetic shell structures. Furthermore, an in-depth parametric analysis is conducted to examine the influence of the hygro-thermal environment on the shell’s stability behavior.
Keywords
Keywords: bio-inspired auxetic core, carbon nanotube-reinforced composite, hygrothermal–torsional stability, nonlinear buckling