The present work quantifies the impact of fuel chemistry on burning modes using premixed dimethyl ether (DME), ethanol (EtOH) and methane flames in a back-to-burnt opposed jet configuration. The study considers equivalence ratios 0 ≤ Φ ≤ 1, resulting in a Damköhler (Da) number range 0.06 ≤ Da ≤ 5.1. Multi-scale turbulence (Re ≃ 19,550 and Ret ≃ 360...
Published in Flow, Turbulence and Combustion
Previous studies have revealed the existence of distinct regimes of DL-stable and unstable turbulent flames, depending on whether the DL instability could be minimized or not. The mechanism of how mixture composition, flame macroscale and turbulence intensity, etc. act on DL instability has been extensively studied. Even though, the role played by ...
Large Eddy Simulations of an unconfined turbulent lean premixed flame, which is stabilised behind a bluff body, are conducted using unstrained flamelets as the sub-grid scale combustion closure. The statistics from the simulations are compared with the corresponding data obtained from the experiment and it is demonstrated that the experimental obse...
Published in Flow, Turbulence and Combustion
Large Eddy Simulations of an unconfined turbulent lean premixed flame, which is stabilised behind a bluff body, are conducted using unstrained flamelets as the sub-grid scale combustion closure. The statistics from the simulations are compared with the corresponding data obtained from the experiment and it is demonstrated that the experimental obse...
Published in Flow, Turbulence and Combustion
It is unclear whether turbulent flame speed scalings established in low speed regimes are applicable to supersonic flames. To investigate this question, the canonical flame kernel is investigated in a scramjet-like channel having a one degree wall divergence. The growth, shape and internal kernel dynamics are investigated. Results are presented for...
Published in Flow, Turbulence and Combustion
The onset of hydrodynamic or Darrieus-Landau (DL) instability can largely impact on premixed flame morphology, turbulent flame speed and induced flow field. In this work, we focus on the latter induced flow by means of two dimensional direct numerical simulations (DNS) of slot burner flames performed in a parametric fashion. Results from linear sta...
© 2016 The Combustion Institute. The interaction of maintained homogeneous isotropic turbulence with lean premixed methane flames is investigated using direct numerical simulation with detailed chemistry. The conditions are chosen to be close to those found in atmospheric laboratory experiments. As the Karlovitz number is increased from 1 to 36, th...
Published in Flow, Turbulence and Combustion
DNS datasets for inert and reactive scalars in statistically homogeneous and stationary turbulence of constant density fluid, and for turbulent premixed flames in an inflow-outflow configuration and in a jet are examined. The objective is to gain a better physical understanding of mixing to use in modeling molecular diffusion terms. Classical descr...
Combustion dynamics of a V-flame in an afterburner-type configuration are investigated using high-order compressible large eddy simulations (LES) and compared to experimental results. Both self-excited longitudinal (100 Hz) and transverse (1400 Hz) modes observed in the experiments are captured by LES and instability mechanisms are discussed. LES r...
Combustion dynamics of a V-flame in an afterburner-type configuration are investigated using high-order compressible large eddy simulations (LES) and compared to experimental results. Both self-excited longitudinal (100 Hz) and transverse (1400 Hz) modes observed in the experiments are captured by LES and instability mechanisms are discussed. LES r...
