Multidimensional Chemistry Coordinate Mapping for Large Eddy Simulations of a Turbulent Premixed Bluff-Body Burner

2025

Vauquelin P., Zhou Y., Åkerblom A., Fureby C. & Bai X.-S.; 2025, “Multidimensional Chemistry Coordinate Mapping for Large Eddy Simulations of a Turbulent Premixed Bluff-Body Burner”, AIAA 2025-2485. doi: 10.2514/6.2025-2485.

https://portal.research.lu.se/sv/publications/multidimensional-chemistry-coordinate-mapping-for-large-eddy-simu

Abstract: In numerical combustion research, accurate chemical reaction mechanisms for heavy hydrocarbons are essential to investigate the flame dynamics of Sustainable Aviation Fuels (SAF) relative to conventional jet fuels. However, accounting for hundreds or thousands of reactions makes Finite-Rate Chemistry (FRC) Large Eddy Simulations (LES) impractical for realistic engineering scenarios. In the present work, a multidimensional Chemistry Coordinate Mapping (CCM) approach is employed to reduce the computational expense of FRC-LES for jet fuel combustion. In the CCM methodology, flow transport equations are Directly Integrated (DI) in the computational cells in physical space, whereas chemical reactions are mapped and integrated in a phase space made up of a few principal variables, improving simulation efficiency. In a turbulent premixed bluff-body burner, the LES-CCM method is compared to experimental data and LES-DI results for conventional Jet A (or A2) and JP5 (or A3) fuels and alternative synthetic fuels, referred to as C1 and C5. Skeletal HyChem reaction mechanisms are utilized, ranging from 40 to 50 species and 200 to 300 reactions. A satisfying compromise is achieved between the accuracy of the results and the speedup factor, up to around five, depending on the CCM phase space dimension and the size of the reaction mechanism.