Simulations of Alpha Wall Load in ITER

For the ITER fusion demonstration, a requirement exists to develop more realistic and reliable simulations of the response of the local thermal wall load to fusion alpha particles, before the wall design is finalized. The concern is that current simulations might underestimate the local wall load. If such an error occurred at only a few hotspots, the current wall design might prove insufficient. This project will add two pieces of new physics ¿ full gyro-orbit dynamics and a realistic model of the ITER wall ¿ to the ORNL code DELTA5D, a drift-orbit-following Monte Carlo code. In Phase I, a full-orbit integrator will be added and a scheme will be implemented for splitting a drift orbit into a set of full orbits, to simultaneously make the simulations efficient and to reduce the statistical noise. Finally, a retrograde Monte Carlo will be investigated to determine if it can suppress statistical noise for this particular application. Commercial Applications and other Benefits as described by the awardee The new simulation technology not only would benefit the ITER project but also would be of use to the broader fusion community. The public would benefit if ITER could show the way to a new source of inexhaustible and environmentally friendly energy, which could help free the U.S. from its current dependence on imported oil.