RESULTS FROM COMPUTATIONAL AND EXPERIMENTAL MODELING OF RUNAWAY ELECTRON DAMAGE ON PLASMA-FACING COMPONENTS

The purpose of this research was to extend the theoretical and experim ental knowledge of runaway electron damage-impact-bombardment on plasm a facing components and materials in magnetic fusion devices. The emph asis of this work involved computational modeling and experimental stu dies to investigate runaway electron energy deposition and thermal res ponse in plasma facing materials. The goals were: 1) to develop a comp utational model to study and analyze runaway electron damage, 2) to ch aracterize runaway electron parameters, and 3) to perform experiments to analyze runaway electron damage. These goals were accomplished by f irst assembling the PTA code package. PTA is a unique application of P ATRAN, the Integrated TIGER Series (ITS), and ABAQUS for modeling high energy electron impact on magnetic fusion materials and components. T he PTA code package provides a three-dimensional, time dependent, comp utational code package which predicts material response from runaway b ombardment under most runaway conditions (i.e., electron energy, incid ent angle, energy density, and deposition time). As part of this resea rch, PTA was used to study energy deposition and material response in several design applications, to analyze damaged material, and to analy ze several experiments. Runaway electron characterization was determin ed through parametric studies, analysis of damaged materials, and anal ysis of experimental results. Characterization provided information on electron energy, incident angle, current deposition time, and volume of material impacted by runaway electrons. Finally an experiment was p erformed on the Advanced Toroidal Facility (ATF) at Oak Ridge National Laboratory to study runaway electron damage. The experiment provided information on the runaway electron energy and current in ATF, as well as supplemented the existing experimental knowledge of runaway electr on damage.