Concurrent topology and fiber distribution optimization of continuous fiber-reinforced polymer (CFRP) structures under thermal-mechanical coupling

Continuous fiber-reinforced polymers (CFRPs) have been extensively utilized in aerospace industries, making it imperative for CFRP structural optimization to consider the effects of extreme service environments. In this paper, a thermal-mechanical coupling concurrent topology and fiber distribution optimization (TM-CTFDO) method is proposed, specifically tailored for CFRP structures subjected to extreme environmental conditions. The mapping relationships between fiber design variables and material properties are deduced based on the rule of mixture to realize the analysis of thermoelastic CFRP structures. The integrated optimization model for CFRP structures is established with minimizing structural compliance, adhering to the volume constraints of structural and fiber under mechanical and temperature loads. Sensitivity analysis and optimization solution are realized by adopting the adjoint method and the method of moving asymptotes, respectively. This approach culminates in the determination of the optimal topology, fiber orientation, and content. In the post-processing phase, a fiber path planning algorithm is investigated to achieve the continuous fiber path based on the optimization results, which also effectively controls the distribution of dense and sparse fiber. Several examples under uniform and varying temperature fields are provided to verify the effectiveness of the TM-CTFDO method. The influence of temperature and mechanical loads on the optimization results is discussed, which will provide guidance on CFRP structural design and fiber path planning under thermal-mechanical coupling.