Parametric design optimization of DTT divertor cassette using a tool for Simulation Process and Data Management

The Divertor Tokamak Test (DTT) project represents a significant milestone in the pursuit of sustainable and efficient nuclear fusion energy. As for any other nuclear fusion experimental machine, the design of DTT components deals with several challenges due to the harsh environment, the demanding mechanical loads and a number of competing requirements. In this context, correctly establishing, from the early design stage, an efficient methodology for parametric design and optimization is of paramount importance. This paper discusses a Systems Engineering approach applied to the design of the DTT divertor cassette, based on a CAD-centric methodology and using an iterative automated workflow implemented in the software modeFRONTIER and VOLTA. The workflow starts from the creation of a parametric model of the divertor geometry, where key dimensional parameters (e.g., dimensions, angles, shapes) are defined as variables that can be adjusted within specified ranges. The design objectives and constraints have been identified, involving mainly structural but also thermal and fluid dynamic aspects. The design space has been explored by modifying the set of driving parameters, therefore, the divertor geometry has been iteratively changed. All the probed geometries have been analysed through FE method. In the performed simulations the EM loads due to a major Downward Vertical Displacement Event have been set up. The whole optimization process has been implemented through VOLTA which is an integration platform for multi-objective and multi-disciplinary optimization. It provides a seamless coupling with third party engineering tools, enabling the automation of the design simulation process, and facilitating analytic decision making. VOLTA integrates with any parametric software (CAD, CAE, FEM, generic, etc.) automating the entire optimization process in which data is transferred from one simulation to the next and the relevant values of outputs and objectives are extracted. The optimization is multi-objective, so the choice of the best design is not immediate. In order to simplify this choice, some tools provided by VOLTA are used. These tools allow to visualize in a better way the trend of the objective and the results.