In gas explosions, the unsteady coupling of the propagating flame and the flow field induced by the presence of blockages along the flame path produces vortices of different scales ahead of the flame front. The resulting flame/vortex interaction intensifies the rate of flame propagation and the pressure rise. In this paper, a joint numerical and experimental study of unsteady premixed flame pro...

Combustion instability is a process which involves unsteady chemical kinetic, fluid mechanic, and acoustic processes. It can lead to unstable behavior and be detrimental in ways ranging from faster part fatigue to catastrophic system failure. In terms of combustion methodology, combustion instability has been a key issue for lean premixed combustion. The primary objective of this work is to imp...

This work focuses upon the effects of DC electric fields on the stability of downward propagating atmospheric pressure premixed propane–air flames under experimental conditions that provide close coupling of the electric field to the flame. With the appropriate electrode geometry, modest applied voltages are shown to drive a stable conical flame first into a wrinkled-laminar flamelet geometry, ...

Laminar flame speeds of undiluted syngas (H2/CO) mixtures have been studied at atmospheric conditions using chemiluminescence and schlieren techniques for a straight cylindrical burner apparatus. A wide range of mixture composition, from pure H2 to 1/99 % H2/CO, has been investigated for lean premixed syngas flames. To achieve a better flame stabilization and reduce flame flashback propensity, ...

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...

Dynamics of outwardly-propagating reaction fronts inspires both fundamental and practical interests. While for the former we can mention in pass supernovae explosions and measurements of laminar flame speeds of reactive mixtures, the latter is relevant to the operation of engines and prevention of spark-initiated hazards such as accidental or intentional explosions. While a pointy-ignited, expa...

Original scientific paper In the numerical simulation research of gas turbine combustor, there are plenty repetitive operations such as modelling and meshing. Parametric design idea is about simplifying it. This paper establishes a parametric modelling system of gas turbine combustor, mainly for the flame tube components, which includes parametric modelling and simple mesh generation. Taking a ...

1. Introduction Premixed turbulent flames are of increasing practical importance and remain a significant research challenge in the combustion community. These flames have the potential to operate cleanly and efficiently over a broad range of fuels, and therefore to represent a key element in the implementation of low-emissions burners for a variety of industrial applications. However, it is di...

In an opposed-jet diffusion flame experiment, under certain conditions, after the extinction of the diffusion flame, an edge flame can be obtained. This ring-shaped edge flame was first reported in 1959 by Potter and Butler but received little attention. It was reported again recently in a numerical and an experimental work and is responsible for an interesting transition between two distinct b...

-The role which low-temperature catalytic combustion should play in the future hydrogen energy system is discussed in comparison with those of conventional flame-type combustion and fuel cells. A hybrid of catalytic and flame combustion is also referred to in the comparison. Screening of catalyst materials proved that several inexpensive oxides of the 3d transition metals were active at interme...