Magnetic field effects on characteristics of counterflow diffusion ethylene flame: An experimental study

The present study was aiming to obtain the effects of magnetic gradients with varying direction on counterflow diffusion ethylene flames, including the flame shape, chemical structure and soot concentration distribution. Experiments were performed using flame imaging with a digital camera, two-color pyrometry, and flame speciation with gas chromatography (GC)/mass spectrometer (MS) system. When upward and horizontal out-ward magnetic gradients were introduced to flames, it was discovered that the mean flame temperature rose and the mean soot concentration dropped in the sooting region, while an opposite trend was observed with the addition of downward magnetic gradient. Meanwhile, results revealed that the presence of the upward or hor-izontal outward magnetic gradients could accelerate the consumption of ethylene and encourage the conversion of intermediate hydrocarbon species to CO and CO2 in the flame area, while the oxidation of fuel and inter-mediate hydrocarbon species were inhibited and the formation of the aromatics was promoted with the appli-cation of the downward magnetic gradient. Furthermore, it was noted that the changing trend of aromatics was consistent with that of soot. The reason might be understood from the variation of magnetic force imposed on oxygen, which in turn affected the fuel consumption and soot distribution.