FLAMENCO (FLow Analysis and Modeling ENvironment with COmbustion) is a well-established high-fidelity solver used for the simulation of turbulent reacting flows with detailed chemistry. The code solves the Navier–Stokes equations augmented with multi-species quasi-conservative advection equations using a structured finite-volume formulation. FLAMENCO employs fifth-order accurate spatial discretisation and a second-order extended stability Runge–Kutta time-integration scheme, enabling the resolution of both low- and high-Mach-number flow features, including shocks and turbulence. Parallelism is achieved through MPI-based domain decomposition, and the code has been demonstrated to scale efficiently to multi-billion-cell simulations on tens of thousands of CPU cores on leadership-class supercomputers. In this talk, we present ongoing research exploring the re-engineering of FLAMENCO using the OPS domain-specific language (DSL) with the aim of enabling performance portability across modern multicore CPUs and GPU-accelerated systems. OPS provides a high-level abstraction for structured- mesh applications, allowing the automatic generation of parallel code for multiple backends while significantly reducing the complexity of architecture-specific performance tuning. This approach enables domain scientists to target diverse hardware platforms without requiring detailed expertise in parallel programming models. We discuss the design considerations, challenges, and methodology involved in porting a large, mature Fortran-based combustion code such as FLAMENCO to OPS, including data layout, stencil representation, and preservation of numerical fidelity. This work lays the foundation for future performance and scalability studies of OPS-enabled FLAMENCO on heterogeneous HPC architectures and aims to facilitate efficient large-scale simulations of complex combustion phenomena such as flame–wall interactions, jets, and stratified reacting flows.
Londhe et al. (2026) studied this question.