This issue presents several facets of a major evolution in digital simulation: the gradual shift toward software platforms combined with the use of increasingly complex development environments. This transformation responds to growing ambitions: to faithfully reproduce the behavior of sophisticated industrial systems—aircraft, space launchers, energy infrastructures—to explore extreme environments where many physical phenomena interact—from atmospheric reentry to nuclear fusion—and to fully exploit the capabilities of next-generation supercomputers. The contributions gathered here testify to the vitality of a field where numerical modeling, high-performance computing, and software engineering converge. Together, these disciplines pave the way for simulation environments capable of addressing multiphysics problems that were previously out of reach.
We also present some of the landmark achievements made possible by these new tools: advances in aerodynamics, innovations in the field of energy, and progress in solving particularly complex coupled phenomena. This issue thus highlights several trends, challenges, and accomplishments that are shaping contemporary numerical simulation.