Coupled simulation of kinetic pedestal growth and MHD ELM crash

Abstract

Edge pedestal height and the accompanying ELM crash are critical elements of ITER physics yet to be understood and predicted through high performance computing. An entirely self-consistent firstprinciples simulation is being pursued as a long term research goal, and the plan is planned forcompletion in time for ITER operation. However, a proof-of-principle work has already beenestablished using a computational tool that employs the best first principles physics available at thepresent time. A kinetic edge equilibrium code XGC0, which can simulate the neoclassically dominantpedestal growth from neutral ionization (using a phenomenological residual turbulence diffusionmotion superposed upon the neoclassical particle motion) is coupled to an extended MHD code M3D,which can perform the nonlinear ELM crash. The stability boundary of the pedestal is checked by anideal MHD linear peeling-ballooning code, which has been validated against many experimental datasets for the large scale (type I) ELMs onset boundary. The coupling workflow and scientific results tobe enabled by it are described.