Direct Numerical Simulation of Turbulent Hydrogen-Air Premixed Flames at Preheated and Diluted Donditions

Wonsik Song, Francisco E. Hernandez Perez, Efstathios-Al. Tingas, Hong Im, Kaust Team

Research output: Contribution to journalArticle


Moderate or intense low-oxygen dilution (MILD) combustion is a promising concept to achieve high-performance and low-emission combustion simultaneously. In this study, we investigate the front propagation and burning characteristics in the MILD mode through high-fidelity direct numerical simulation (DNS). As a baseline condition, a lean hydrogen-oxygen mixture at an equivalence ratio of 0.7 is considered, which is diluted with nitrogen and preheated. The turbulence parameters such as the integral length scale and RMS velocity are set to ten and five times larger than the laminar flame thickness and flame speed (lT /lf = 10, u ' /SL = 5 . 2), respectively, such that the turbulence condition falls under the thin reaction zone in the so-called Borghi diagram of premixed combustion. Fundamental turbulent combustion characteristics including burning rate, flame structure and topology are examined, together with intrinsic hydrodynamic and diffusive-thermal instabilities. Research reported in this publication was supported by the King Abdullah University of Science and Technology (KAUST).
Original languageEnglish
Article numberG05.002
JournalAPS Division of Fluid Dynamics (Fall) 2019
Publication statusPublished - 1 Nov 2019


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