Additively manufactured inconel 718 vapor chamber with conformal micro-pillar wicks: A low temperature concept demonstration

Abstract

Effective thermal management is crucial in hypersonic flight (Mach > 5) due to extremely high aerodynamic heating located at leading edges, and both passive and active thermal protection systems (TPS) have been used to address this. Among passive TPS options are two-phase thermal management systems, such as heat pipes (HP) and vapor chambers (VC), which can realize a considerable reduction in steady-state leading edge temperature owing to their extremely high heat transfer capability. This leads to reduction in complexity and cost of TPS structure and material requirements. However, conventional HP and VC fabrication methods require multiple manufacturing and assembly steps, limiting their design space. Alternatively, utilizing additive manufacturing (AM) for fabrication can bypass conventional manufacturing limitations and enable structural members with intricate internal channels and topologically optimized shapes. AM can, therefore, unveil a larger design space for tailored leading edge concepts with an integrated passive TPS. This work demonstrates the design, fabrication and testing of a notional methanol-filled Inconel 718 VC with a conformal micro-pillar wick fabricated via laser-beam powder bed fusion AM. This serves as a proof of concept and establishes a foundation for design and fabrication of high-temperature additively manufactured sodium-filled leading edge VCs.