Nitrogen-Diluted Methane Flames in the Near-and Far-Field

Abstract

With the increased utilization of multicomponent fuels, such as natural gas and biogas, in industrial applications, there is a need to be able to effectively model and predict the properties of jet flames for mixed fuels. In addition, the interaction of these diluted fuels with outside influences (such as differing levels of coflow air) is a primary consideration. Experiments were performed on methane jet flames under the influence of varying levels of nitrogen dilution, from low Reynolds number lifted regimes to blowout, observing the influence of the nitrogen on lifted flame height and flame chemiluminesence images. These findings were analyzed and compared with existing lifted jet flame relations, such as the flammable region approximation proposed by Tieszen et ai, as well as to undiluted flames. The influence of nitrogen dilution was seen to have an effect on the liftoff height of the flame, as well as the blowout velocity of the flame, but was seen to have a less pronounced effect compared with flames with coflowing air.

Effects of Electric Fields on Stabilized Lifted Propane Flames

“…Various other external influences, such as an ambient air cofiow [17,[21][22][23], jet confinement/recirculation [24][25][26], inert dilution [22,[27][28][29][30][31], and enrichment [32,33] impact flame behavior. Lee et al [1] found that an alternating current applied to a turbulent propane flame decreases liftoff height and delays liftoff, thus, increasing flame stability; however, for direct current, the impact on the flame stability was minimal.…”