Design, Simulation and Virtual Certification Assessment of a Medium Range Aeroengine Combustor

Here we present the integrated design, high-fidelity simulation, and virtual emission-certification of a medium-range aero-engine combustor developed within the EU-funded MYTHOS project. The objective is to establish a physics-based framework capable of predicting combustor behavior for both conventional fuels and emerging Sustainable Aviation Fuels (SAF). Starting from a 0D thermodynamic cycle, a Rich-burn–Quick-mix–Lean-burn (RQL) annular combustor was conceived for a medium-range twin-spool turbofan and equipped with Triple Annular Research Swirler burners. A single-burner sector was then evaluated for Jet A fuel under realistic Cruise, Approach, and Take-Off conditions. Reactive Large-Eddy Simulations with Finite-Rate Chemistry (FRC-LES) were performed, combining Lagrangian Particle Tracking, Partially-stirred reactor (PaSR) turbulence–chemistry coupling, and a compact Z79-Jet A/NOx mechanism. Mesh sensitivity studies using three meshes of 12, 22, and 46 million cells showed that the global flow and flame topologies are well reproduced on intermediate resolution, whereas accurate prediction of minor species requires the finest grid. The simulations demonstrated the various flame regimes in the cruise and off-design conditions in mixture-fraction–temperature space, exhaust pattern factors and emission indices. The predicted CO and NOx levels follow the qualitative hierarchy of the certified CFM56-7B22E engine. The resulting configuration and methodology establish a robust baseline for forthcoming studies on SAF effects, coupled combustor–turbine simulations and, ultimately, the development of a virtual Open Research Engine platform.