Design and Mechanical analysis of a compact heat exchanger with Triply Periodical Minimal Surface realized by Additive Manufacturing.

In space applications, state-of-the-art heat exchangers , with top performance for their entire lifetime, minimizing the risk, are to be designed under strict size and weight constraints. Here a compact heat exchanger, designed with gyroids, an innovative Triply periodical minimal surface (TPMS) topology, is considered. This family of compact heat exchangers represents a major step forward in thermal management, thanks to their small footprint and the high heat transfer performance they can achieve. Due to their peculiar internal structure, they cannot be produced using traditional technologies but they must rely on Additive Manufacturing technique, an exponentially growing technology in recent years but at the same time immature in terms of achieving the 'state of the art'. The aim of this thesis is to perform an innovative design and a structural analysis of the compact heat exchanger with gyroids, comparing different geometries and materials, to find the right compromise that can meet product repeatability, with the performance required for the exchanger by solving the problems dictated by the production technology. It has therefore been found that the best compromise, combining reliability, light weight and a good heat exchange, is to create a CHX with a prismatic structure, the heart of which is formed by TPMS cells in a gyroid configuration with a 15mm side.