Characterization of 1-butanol electrospray combustion

butanol;electrospray;combustion;spray

Pennisi, Michael ; Kyritsis ; Dimitrios C.

关键词: butanol;    electrospray;    combustion;    spray;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/31107/Pennisi_Michael.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

This study examined the characteristics of electrosprays of 1-butanol that burn in air. Still images and high-speed movies captured with a laser sheet present helped to establish general flame phenomenology and features such as shape, size, and stability of the spray flame. The dependence of the flame structure and stability on butanol flow rate and the applied voltage were examined. Mie-scattering-based droplet size measurements were performed in both reacting and non-reacting electrosprays. In general, a large peak in the distribution of droplet diameters centered between 40 and 50 micron was observed in the non-reacting case, with a second peak observed around 200 and 300 micron.With the flame present, a broader size distribution, still with a peak between at 40 and 50 micron, but with a larger proportion of 20 to 50 micron droplet diameters were seen. In addition, high-speed velocimetry measurements provided insight into the velocity of the droplets inside the burning spray. Some droplets were observed not to vaporize completely and pass through the flame. Photographic evidence was acquired of droplet fission in the burning spray. Charge transferred by the spray was also measured and compared with the Rayleigh limit criterion for droplet fission. An analysis of the evaporation time, based on droplet size and velocity, was used in order to rationalize the results. Indeed, large droplets traveling with velocities observed in the high speed films could pass through the flame without completely evaporating. It was concluded that the electrosprays of bio-butanol could sustain flames stabilized with the assistance of electrostatics. Furthermore, these electrospray flames had characteristics substantially different from the spray flames of non-charged fuels.