Numerical Simulations of the Plasma Parameters in the SPIDER Device

This article presents the basic physical and numerical principles of a fluid model implemented into the numerical code fluid solver for SPIDER in 2D (FSFS2D) used for simulations of the source for the production of ions of deuterium extracted from RF plasma (SPIDER) negative ion source. It gives self-consistent 2-D description of the source, including the neutral gas flow, plasma chemistry, radio frequency (RF) coupling in the source driver, and plasma transport through the magnetic filter (MF). In order to capture the neutral depletion and its impact on the plasma dynamics the continuity equation for molecules and the corresponding surface chemistry have been included in the model. An important element in the development of the numerical framework is the validation of the code results against the experimental data. For this aim, a series of numerical simulations have been performed and compared with the experimental data from the SPIDER experimental campaigns. This article presents critical assessment of the validation results and outlines the necessary code/model enhancements required to improve the predictive capability of the FSFS2D code.