Investigation of thermoelastic compliances considering finite strain

• Published in: Computer methods in applied mechanics and engineering 2023-05, Vol.410, p.116011, Article 116011
• Main Authors: Goh, Byeonghyeon, Kim, H. Alicia, Chung, Hayoung
• Format: Article
• Language: English
• Subjects: End compliance; Finite strain theory; Strain energy; Thermoelasticity; Topology optimization
• ISSN: 0045-7825; 1879-2138
• DOI: 10.1016/j.cma.2023.116011

Topology optimization of thermoelastic structures is of significance in many engineering applications such as for additive manufacturing, metamaterials, and soft robotics. To ensure that a structure performs adequately over a wide range of thermoelastic loading conditions and thermal expansion, incorporating the finite strain theory in the design strategy is critical. In this study, we investigate the two energy-based objective functions, namely the end compliance and strain energy under thermomechanical conditions. The numerical examples considered indicate that the optimized layout is highly dependent on the selected objective function; such differences among the layouts can be attributed to the manner in which the structure accommodates the changing temperature. The end compliance is minimized by leveraging the direction of the thermal load to offset the mechanical load, while the minimization of the strain energy contributes to the strength of the structure by limiting the thermal contribution to the overall stress within the structure. Furthermore, we show the effects of different strain assumptions on the optimality of layouts. Thus, this study reveals the significance of adopting each thermoelastic compliance and highlights the importance of accounting for structural nonlinearity when considering the thermal effect.