Turbulent-flame speeds in methane–air mixtures were measured in a Taylor–Couette apparatus with counter-rotating cylinders, used to generate turbulence that is nearly homogeneous and isotropic over many integral length and time scales. While laminar-flame propagation is found to be influenced by the Darrieus– Landau instability and heat loss to the walls of the apparatus, turbulent-flame propag...

Performing high-fidelity simulations of complex reacting flows requires that the uncertainties associated with predictions of fundamental flame properties are characterized and minimized. Although the kinetics of C1-C4 hydrocarbon flames have been studied extensively in numerous past investigations, notable uncertainties exist. In the present study, the types of hydrocarbon fuels with the great...

We present the use of simultaneous Particle Streak Velocimetry (PSV) and CH Planar Laser Induced Fluorescence (PLIF) diagnostics in the study of planar, strained, premixed, methane-air flames, stabilized in a jet-wall stagnation flow. Both PSV and PLIF data are imaged at high spatial resolution and sufficiently high framing rates to permit an assessment of flame planarity and stability. Concurr...

The unresolved Q-branch profiles in the Raman spectra of' nitrogen in premixed, laminar, methane-air, propane-air and butane-air flames with lean to stoichiometric fuel-air equivalence ratios have been recorded experimentally and used to determine flame temperature s with a precision of about 10f0using an iterative computer program which fitted calculated nitrogen spectra to the experimentally ...

The description of chemical kinetics in turbulent reactive flows is an important task to improve combustion models. This paper describes the inclusion of detailed chemical reaction mechanisms into the framework of a turbulent flame simulation. Calculations are based on a finite-volume solution procedure including submodels for turbulent flow, combustion of fuel and radiative heat transfer. The ...

This paper reports an experimental investigation of premixed propane and methane-air flames propagating freely in tubes 1.5 m long and with diameters 54 and 94 mm. Two regimes of propagation are distinguished by correlating the flame speed and the radius of curvature at the flame tip. The characteristic lengths are then related to the cut-off wavelengths estimated from linear theories and compa...

Diamond growth using a new low-pressure combustion technique is reported. A large-area hydrogen/oxygen flame is used as the source of atomic hydrogen. Methane diluted in hydrogen is injected into the flame near a heated silicon substrate, on which diamond crystallites nucleate and grow. This technique is potentially capable of large-area film growth, since atomic hydrogen can be generated unifo...

Experimental and numerical techniques to characterize the response of premixed methane-air flames to acoustic waves are discussed and applied to a multi-slit Bunsen burner. The steady flame shape, flame front kinematics and flow field of acoustically exited flames, as well as the flame transfer function and matrix are computed. The numerical results are compared with experiments. The influence ...

Direct numerical simulations of two-dimensional unsteady premixed methane/air flames are performed to determine the correlation of flame-speed with stretch over a wide range of curvatures and strain rates generated by intense two-dimensional turbulence. Lean and stoichiometric premixtures are considered with a detailed C1-mechanism for methane oxidation. The computed correlation shows the exist...

A new analytical study performed to investigate the effect of the temperature difference between gas and particle in propagation of the spherical flames. The combustible system is containing uniformly distributed volatile fuel particles in an oxidizing gas (Air) mixture. The model includes evaporation of volatile matter of dust particles to known gaseous fuel (methane) and the single-stage reac...