Disruption Simulation Code for Tokamaks and ITER Applications

Arguably the most important issue facing the further development of magnetic fusion via advanced tokamaks is to predict, avoid, or mitigate disruptions. This problem recently becameone of the most challenging and hot topics in fusion research due to several potentially damaging effects, all of which can impact the ITER device. Among four disruption related topics: MHD dynamics, plasma edge physics, plasma-wall interaction physics and generation and losses of runaway electrons, the DSC addresses the firstone. The numerical algorithm will allow extension in physics models and interface with otherrelevant codes. DSC will solve the resistive one fluid 3D MHD equations in the real geometry ofthe conducting tokamak vessel, utilizing the adaptive meshless technique and will finally beparallelized. The DSC will be validated against the JET disruption data and will be capable ofpredicting the disruption effects in ITER. DSC will contribute to the development of the disruption mitigation schemes and suppression of the runaway generation. The DSC code was implemented in 2D with all basic components of the full 3D version. It performs adaptive, meshless free-boundary plasma core simulations. Vacuum fields, the plasma surface and wall currents are calculated using both Green & apos;s functions and Poisson equation methods. For the first time the non-linear dynamics of the wall touching kink mode was simulated, including both fast ideal MHD regime till the saturation due to excitation of the Hiro currents, and the slower regime of the current quench due to resistive decay of the Hiro currents. A full one-fluid 3-D resistive MHD DSC will be developed capable of implementing realistic 3Dmodels of in-vessel components of tokamaks (e.g., LTX, JET, ITER, DIII-D, NSTX, J-TEXT). The m=1 kink mode simulations will be validated against JET disruption data base. Commercial Applications and Other Benefits: The DSC extends an innovative adaptive meshless method to a new area of application. DSC willmake a unique and timely contribution to the US and International tokamak fusion programs. With the projects completion, the DSC will result in a powerful simulation tool, available anddeliverable to the fusion energy science community. Being experimentally verified, the DSC can be a part of the software suite of the currently proposed Fusion Simulation Project (FSP).