A new design approach for thermal actuators based on topology optimization with stress constraints

Abstract

This paper proposes a new approach for the design of thermal actuators using topology optimization. For the designs based on topology optimization, compliant mechanisms are required to have flexible, stiff, and sustained structures. To achieve this, conventional methods usually consider multiloading problems or use spring elements. In this work, a method that only considers one load case and does not use spring elements was developed by introducing an objective function that combines evaluation functions that provide necessary features for the actuators. This way, a structure with the same deformation mode of real phenomena could be derived with a low computational cost and without spring elements. In addition, the stress constraints on the thermal stress, which have not been widely discussed so far, were applied to show the structure with the considered strength characteristics. The study subject is topology optimization of an isotropic thermo-elastic model considering a thermo-mechanical problem. Finally, numerical examples for multiple conditions were performed to show that the proposed method can derive the desired optimal structure.