Generative AI Meets Legacy HPC Codes: Local, Frugal and Confidential AI Assistance for Scientific Software

Within EXCELLERAT, the CFD code CODA, developed by DLR, ONERA and Airbus, was successfully optimised for modern GPU-based High-Performance Computing (HPC) systems. By significantly improving the scalability of the Sparse Linear Systems Solver (Spliss), CODA can now efficiently scale across hundreds of GPUs, achieving speedups of up to 8.6× compared to state-of-the-art CPU systems. This enables larger, higher-fidelity aerodynamics simulations in weeks instead of months and prepares CODA for current and future heterogeneous and exascale HPC systems, supporting the design of quieter, safer and more fuel-efficient aircraft.