Design, Manufacturing, and Experimental Characterization of a First-of-a-Kind DTT ECH Mirror Equipped With TPMS

The design, manufacturing, and experimental characterization of the prototype of an electron cyclotron heating (ECH) mirror equipped with an innovative cooling system based on triply periodic minimal surfaces (TPMS) is presented here. The prototype, manufactured in AISI 316L via selective laser melting (SLM), is engineered to withstand high heat fluxes and to mitigate eddy currents induced during tokamak operation. The TPMS cooling structure features a Gyroid topology with variable cell size. Hydraulic and thermal tests were conducted in a dedicated water loop, and experimental results were compared to numerical predictions. The measured pressure drops were worse than those calculated, probably due to surface roughness and geometrical deviations, and can be reproduced numerically with a geometry with an effective porosity lower than the nominal one. The thermal measurements, on the other hand, appear to be quite far from the simulations, probably due to the influence of the experimental setup on the thermocouple readings. These findings confirm the potential of TPMS-based cooling for ECH mirrors and highlight areas for further improvement in manufacturing, modeling, and testing.