The performance of nekCRF has been shown to surpass that of other state-of-the-art reactive flow solvers, particularly in the context of real-world exascale use cases. In comparative studies, nekCRF demonstrated significant speedup factors, achieving up to 22 times faster performance than its predecessor, LAVp, under optimal conditions. This performance advantage is attributed to several factors, including its optimized thermochemistry solver, which utilizes advanced techniques for Jacobian evaluation and linear solving, as well as its efficient handling of GPU architectures.
Moreover, nekCRF's ability to support high-order spectral element methods allows for reduced numerical diffusion and dissipation, which is critical in accurately capturing the dynamics of turbulent flows. This capability is particularly beneficial in direct numerical simulations (DNS) of combustion processes, where the accurate representation of energetic structures is essential.
In addition to raw performance metrics, nekCRF's scalability on GPU-based systems has been validated through extensive testing on platforms like JUWELS Booster. The solver has shown strong scaling capabilities, maintaining high parallel efficiency even as the number of compute nodes increases. This is a crucial advantage in exascale applications, where the ability to efficiently utilize a large number of processing units is essential for tackling complex simulations.
Overall, nekCRF's combination of high performance, scalability, and flexibility in handling complex geometries and chemical kinetics positions it as a leading tool in the field of reactive flow simulations, particularly in the context of exascale computing challenges.