Parametrical modelling and assessment of tokamak maintainability

The system design models of tokamak fusion reactors can be parameterized and coupled to enable holistic code-based exploration and optimization of tokamak geometry. System codes have been developed for the major systems of the tokamak, but some systems such as the Remote Maintenance (RM) system have not been extensively codified. Development of RM systems has largely remained a decoupled process. We explore parameterization of Computer Aided Design (CAD) models and feasibility assessment scripts as the means to introduce a method to assess maintainability as a quantifiable optimization goal in the early convergence loop of tokamak geometry. Several tokamak design points have been studied that provide reference cases to approximate and link input and output parameters for the RM system design. EUROfusion DEMO is used as a basis for generating the CAD model, but we remain agnostic to tokamak configuration variations while exploiting and linking historical design data. The aim of the presented work is to accelerate and harmonize the creation of variations of the tokamak geometry coupled with numerical maintainability evaluation for plant architecture assessments. Hierarchical skeleton-based modelling methodology is utilized to model a responsive parameterized tokamak including geometrical elements of the RM system and installation paths of In-Vessel Components. Parallel to the development of the CAD model we construct a script to collate and export RM feasibility assessment values. The RM feasibility assessment is based on a selection of individual feasibility criteria, and mapping of the criteria to geometrical elements of the CAD model. The criteria effects are normalized and combined to provide converged feasibility values for tokamak design points. Range of design points are generated with the parametrical model and assessed utilizing the assessment script.