High Conductive Load-Bearing Sensorcraft Skin Design for Thermal Energy Transport and Harvesting

This article introduces the design process of a multi-functional skin structure for thermal energy transport and load bearing by using topology optimization. A single cell with periodic boundary conditions in the in-plane direction is used as a design space so that the final single-cell design can be repeated to construct a continuous sheet of material. The newly engineered skin is developed using two materials to meet two required functionalities of a Sensorcraft wing skin; one is to maximize the conductivity of the skin in thickness direction in order to dissipate internal heat into the air, sink, and minimize the inside skin surface temperature passively, thereby, allowing the thermoelectric device to operate at an optimum condition. The other is to maximize the in-plane stiffness to provide the load-bearing capability of the skin to an external load such as torsion. A multi-functional optimization scheme using a linear combination of two objective functions with weights is used to find the optimal layout of the two materials. A specimen was manufactured and multiple-cell analysis of aluminum block, plug configuration, and optimal configuration was conducted to compare the temperature-convergence history according to the number of cells.