Fast generation of parametric neutronic models for stellarators. Coupling HeliasGeom and GEOUNED

The operation of the Wendelstein 7-X has highlighted stellarators as potential fusion power reactors. As a consequence, the pre -conceptual design of the next HELIAS stellarator has started in the framework of EUROfusion. During these first stages, it is essential to assess the feasibility of various stellarator concepts. It is important to emphasize that these concepts can vary significantly in terms of their overall shape and allocation of space for each component, including the vacuum vessel, breeding blankets, among others. Although pre -conceptual neutronic analysis can be conducted using straightforward yet representative neutronic models, such as simplified multilayer models with minimal geometric details, the intricate shape of stellarators presents challenges to produce them quickly. This issue prevents the effective parametric optimization of the concepts, creating a bottleneck in the design of HELIAS. In order to overcome this problem, we are developing a computational workflow for the fast production of parametric stellarator neutronic MCNP models. This work presents the current status of the scheme composed of two steps: HeliasGeom for the production of parametric multilayer CAD models, and GEOUNED for the translation of these models to MCNP CSG neutronic models.