화학공학소재연구정보센터
International Journal of Hydrogen Energy, Vol.41, No.4, 3208-3221, 2016
A numerical investigation of structure and NO emissions of turbulent syngas diffusion flame in counter-flow configuration
This paper reports a numerical simulation of turbulent non-premixed counter-flow syngas flames structure and NO emissions at a high strain rate with a special focus on mixing. The analysis is conducted over a wide range of hydrogen percentage (H-2/CO ratio between 0.4 and 2.0) and operating pressure (from 1 to 10 atm). Numerical model is based on RANS (Reynolds Averaged Navier Stokes) technique including k-epsilon turbulence model. SLFM (Steady laminar flamelet model) is used for flame structure calculations and EPFM (Eulerian Particle Flamelet Model) is applied for NOx predictions. Mixing is described by mixture fraction and its variance. Radiation effects are also considered. Computational results show an improvement of mixing with hydrogen enrichment and ambient pressure rise. Maximum flame temperature decreases with H-2 addition and increases with pressure. NO levels decrease towards hydrogen-rich syngas flames and increase with pressure. Zeldovich route is found to be the main NO formation path in the operating conditions considered. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.