Water emulsified fuels are used in many combustion systems including internal combustion engines and gas turbines to suppress NO_x emission and flame characteristics. When emulsified fuel droplets impinge onto a high temperature surface such as the wall of a combustion chamber, their breakup and ignition phenomena may differ from those of ordinary fuels. In this study, water emulsified n-dodecane was prepared with various mixing ratios, and its single droplet was impinged onto a hot plate surface that consists of a quartz plate channel and a methane-air flame inside. Thus, the surface temperature could be increased up to about 1080K. After impinging of emulsion droplet, detailed phenomena of breakup and ignition were experimentally investigated, and were visualized using a high-speed camera. The effects of the droplet size, velocity, and volume fraction of n-dodecane, X_(dod), were investigated. When the surface temperature was higher than the boiling temperature, various breakup-patterns could be observed depending different conditions. In addition, diffusion flame could be observed after breakup of the emulsion droplet. The conditions and mechanisms of ignition were investigated.
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