Effective reduction on flame soot via plasma coupled with carbon dioxide.

This study explored the impact of non-thermal plasma and CO on the flame soot characteristics within the diffusion flames. We analyzed on flame structures that were diluted with either CO or N, temperature distributions, and soot characteristics, both in the presence and absence of plasma. Due to the higher specific heat capacity of CO compared to N, the optical observations consistently showed lower temperatures in flames diluted with CO as compared to those diluted with N.

Formation and Evolution of Soot in Ethylene Inverse Diffusion Flames in Ozone Atmosphere.

Ozone is a prospective additive for enhancing and controlling combustion under lean or very lean conditions, and reduces NOx and particulate matter emissions simultaneously. Typically, in studying the effects of ozone on combustion pollutants, the focus is on the final yield of pollutants, while its detailed effects on the soot formation process remain unknown. Here, the formation and evolution profiles of soot containing morphology and nanostructures in ethylene inverse diffusion flames with different ozone concentration additions were experimentally studied.

Edge Effects on Simultaneous Reconstructions of Flame Temperature and Soot Volume Fraction Profiles by a CCD Camera.

In this paper, the influence of the edge effect on the simultaneous reconstruction of axisymmetric flame temperature and soot volume fraction profiles by a single CCD camera was investigated in detail. The reconstruction accuracy of the flame temperature profile and soot volume fraction was insensitive to the measurement error of the coefficient matrix. When the signal to ratio () of the measurement system for both the radiation intensity and coefficient matrix was as low as 46 dB, the reconstruction accuracy for both temperature and soot volume fraction was acceptable and was more influenced by the radiation intensity measurement error.

Quantitative optical diagnostics on macroscopic soot onset for ethylene diffusion flames with ethyl ester addition.

A novel quantitative optical diagnostics method for determining the threshold of soot onset in counterflow diffusion flames was proposed and demonstrated. The method was based on the proportional discrimination of trichromatic luminescence and the nonparametric and unsupervised automatic threshold selection algorithm. The macroscopic soot onset threshold in ethylene diffusion flame with three ethyl esters additions could be precisely determined.

Effects of diluent gases on sooting transition process in ethylene counterflow diffusion flames.

The impacts of adding diluent gases (nitrogen, carbon dioxide, and helium) either to the fuel side or the oxidizer side on the sooting transition process in ethylene counterflow diffusion flames are investigated experimentally and numerically. A series of ethylene flames ranging from non-sooting to heavy-sooting are studied by gradually increasing the oxygen concentration on the oxidizer side. The optical method is used to analyze flame images, determining the sooting transition process.

Soot reduction by addition of dimethyl carbonate in normal and inverse ethylene diffusion flames: Nanostructural evidence.

Oxygenated fuel represents an attractive alternative as an additive for reducing soot emissions. Dimethyl carbonate (DMC) is an oxygenated compound which is a good option to reduce soot, but the detailed characteristics of soot produced from combustion of hydrocarbon fuels blended with DMC are still lacking. The present research studied the nanostructure and reactivity of soot particles in ethylene/DMC normal and inverse diffusion flames.