TY  - JOUR
AB  - Purpose– The present paper is about numerical simulations of one‐ and two‐dimensional lean hydrogen combustion at an equivalence ratio of 0.7. The initial flat two‐dimensional flames show unstable behavior. The instabilities generate flame wrinkling and flame induced turbulence. As a result, cusp‐like structures arise that both merge and break up in new cusps. Therefore, physically, the laminar burning velocity associated to an adiabatic flat flame does not exist. Instead, a statistical effective burning velocity and flame width develop in which the cusp like structures and their effects are included. The purpose of this paper is to describe the phenomena with a reduced chemical approach.Design/methodology/approach– Simulations are performed with detailed kinetics, to study the main properties and dynamics of the wrinkling. An attempt is made to reduce the chemistry employing flamelet generated manifolds to make a step towards large‐scale, low cost simulations, which are still able to capture the physics. Here the manifold was built of premixed flames with variations of stretch, unburnt temperature and equivalence ratio. A priori correlations are presented, together with results from actual reduced chemistry simulations.Findings– It was found that with introduction of variation of equivalence ratio into the manifold the main physical phenomena are captured. Moreover, an effective inclusion of differential diffusion was succesfully tested and applied. Results of effective burning velocities and flame widths are presented.Originality/value– The paper shows the potential of performing accurate simulations using the chemical reduction technique of flamelet generated manifolds for pure lean hydrogen flames.
VL  - 22
IS  - 1
SN  - 0961-5539
DO  - 10.1108/09615531211188829
UR  - https://doi.org/10.1108/09615531211188829
AU  - Bastiaans Rob
AU  - Vreman A.W.
PY  - 2012
Y1  - 2012/01/01
TI  - Numerical simulation of instabilities in lean premixed hydrogen combustion
T2  - International Journal of Numerical Methods for Heat & Fluid Flow
PB  - Emerald Group Publishing Limited
SP  - 112
EP  - 128
Y2  - 2024/04/19
ER  -