Due to the fast growth of biodiesel production capacity, the amount of glycerol has increased rapidly. Furthermore, the supply of glycerol has exceeded the demand needs in the market. In addition, there is a great demand for finding other new applications and ways to discard glycerol in an environmental friendly manner. One of innovative methods is to use glycerol as a liquid fuel in cogeneration and power generation. If it used properly, it could reduce the demand for conventional fossil fuels in those applications. However, glycerol has a very low vapor pressure and relatively high flash point values when compared to diesel and biodiesel. Therefore, ways to disperse and combust glycerol droplet should be researched. Recently, researchers have revealed that microexplosion occurs in binary fuel mixture droplets under specific temperatures since droplets consist of two liquids with different boiling point values. This phenomena can lead to higher combustion efficiency and a reduction of NOx emissions even when combusting glycerol-based mixtures. In this research, microexplosion phenomena of methanol-in-glycerol mixtures have been studied using a high speed camera and an acoustic sensor system. A Fast Fourier Transform (FFT) algorithm has been used to analyze the collected data using Matlab to understand frequencies of microexplosion. The main goal of this study is to find the highest probability of microexplosion occurrence under the certain temperatures and to understand the relationship between frequencies of microexplosion and droplet size. Methanol-in-glycerol mixtures with 5%, 10%, and 15% methanol were prepared and tested in a microexplosion chamber. Also, water-in-glycerol mixtures with 50% water were mixed and compared with the results of methanol-in-glycerol mixtures. Droplet sizes were controlled at 230 um and 130 um using nanoparticle based coatings to be able to understand the effect of discrete droplet size on microexplosion properties. The results indicate that temperature has a strong effect of the probability of microexplosion. Furthermore, bigger droplet size (230 um) depicts higher probability of microexplosion occurrence than 130 um droplets. In addition, the frequencies of microexplosion were measured under the temperature with the highest microexplosion probability. Furthermore, droplets with higher concentration of methanol exhibit higher microexplosion frequency. Size of droplet is also a significant factor that affects frequencies with smaller droplets exhibiting higher frequencies. Future studies will consider smaller droplets and other fuel mixtures.
