Introducing FREDA: an integrated physics and engineering tool for fusion reactor design, assessment, and optimization

The fusion reactor design and assessment (FREDA) project aims to use integrated simulation to shorten development time and guide design decisions to quickly arrive at innovative solutions that maximize the probability of meeting Fusion Pilot Plant (FPP) goals and enable optimization to impact commercial viability and timely delivery of fusion power. FREDA is not just a collection of codes: it is a purpose-built framework being developed to catch 'show-stoppers' in the design at the appropriate fidelity level, with self-consistent workflows that range from optimization over large parameter space scans, to individual component design iteration, to high-fidelity, whole-device assessment. The backbone is IPS-FASTRAN with newly developed coupled Core-Edge Pedestal-SOL (CESOL) workflows, which is being extended to the far-SOL region up to the plasma facing components. It includes tightly coupled nuclear and structural engineering modeling of the first wall, blanket, magnets, etc. Rapid component optimization is enabled by parametrized engineering, where geometry is generated by codes, not people. The scripted auto-generation of blanket CAD for the DCLL ceramic breeder blanket concept has been incorporated as an example. As a demonstration of the iterative design process, a compact high power density tokamak design point is optimized in aspect ratio to achieve high fusion power density and low recirculating power while satisfying basic geometric engineering constraints.