Numerical error estimation in Random Noise coupled plasma edge simulations in nuclear fusion reactors

The plasma edge in nuclear fusion reactors is simulated using a coupled finite volume / Monte Carlo code. To unravel error contributions from such coupled simulation technique, a framework for error assessment has been developed. It was successfully applied to Random Noise simulations, where the trajectories in the Monte Carlo code are completely uncorrelated each iteration. However, difficulties were encountered in the estimation of the statistical error and the determination of the onset of steadiness. In this paper, several methods are examined to deal with these difficulties, leading to practical methods, which can be easily implemented.