Performances of the CFD open-source HPC platform TRUST on GPUs

TRUST is a versatile open-source CFD tool developed by the CEA since 1993. Initially designed for nuclear applications, TRUST has evolved to tackle a range of thermohydraulic challenges, from one-phase to multiphase flows. It offers various numerical methods and supports different mesh types for efficient computation on diverse computing platforms, including high-performance computers. Recently, efforts have been made to integrate GPU computing libraries like AmgX, rocALUTION, and Kokkos aiming for a hybrid CPU/GPU code achieving better performance portability. This paper provides an overview of the TRUST platform, discusses its GPU computing strategy, and presents selected associated results.