Development of Tunable Resonant Trays for Dust Collection in Tokamaks

During tokamak operations, a significant amount of erosion occurs on the plasma facing components. This results in the accumulation of dust primarily within the machine’s lower divertor. In large scale projects such as ITER, this poses a challenge for sustained fusion operations. We propose a solution for actively removing the accumulated material based on tuned resonant trays for the collection and displacement of this dust to discharge ports. Based on linear vibrating powder feeders implemented on the Impurity Powder Dropper [Nagy RSI 2018], these tunable trays offer a potential dust management solution during tokamak operations. The resonant response of key assembly components was modeled by computer simulations for multiple materials and geometric configurations. The modeled results were validated by dedicated bench top testing using a piezo drive and accelerometer combination in order to properly characterize the acoustic response of the system. Leveraging these results, a full model has been designed, scaled for installation on a mid-size tokamak, compatible with the constraints of a high vacuum (10^-7 Torr) and high temperature (~400C) environment. This work aims to show that these trays are a cost effective, scalable, and enabling technology for future tokamak devices.