Theodore Biewer: The Development of Digital Holographic Imaging at ORNL to Study Material Surfaces Inside Fusion Reactors During Plasma Exposure
As we have traveled down the road towards a viable nuclear fusion reactor, we have made plasma discharges of increasing duration and intensity. The baseline operational scenario for the International Tokamak Experimental Reactor (ITER), which is currently under construction, is expected to produce plasma heat fluxes to material surfaces of ~10 MW/m^2 for 1 hour discharges. Laser-based diagnostic techniques have become commonplace in today’s plasma devices, but new techniques are being developed to provide unprecedented details, especially at the plasma-material interface.A diagnostic is being developed at Oak Ridge National Lab, which uses lasers to produce holographic images of material surfaces in a fusion relevant device, during the period of plasma exposure, and could possibly even provide real-time control information to future reactor safety systems. A description of digital holography will be give, as it is being developed for the Material Plasma Exposure eXperiment.