Design of Additively-Manufactured Lattice Structure for Thermal Protection System: Thermal Characterization and Transient Performance

摘要

Lattice structure can decrease the apparent thermal conductivity of material produced by Additive Manufacturing (AM) technology. To design the insulating layer for Thermal Protection System (TPS) with lattice structure, it is critical to consider both effective thermal conductivity and diffusivity of the structure. The study intends to explore the impact of lattice topology on the global transient insulating performance. Four different lattice designs: solid, simple cube, semi-fishbone (I-channel and C-channel), and hybrid design are compared by measuring their apparent thermal conductivity and heat-soaked temperature in transient heating test. All lattice structures design shows lower apparent thermal conductivity compared to solids. The simple cube has the lowest averaging apparent thermal conductivity (0.185 W/(mk)), followed by hybrid (0.215 W/(m·k)), and C-channel design (0.229 W/(mk)). During the transient heating test, the hybrid design shows lower backside temperature (38.645 °C ) than solid (average backside temperature: ～45 °C ) and demonstrates the global distribution of lattice structure can vary the insulating capability for TPS designs.