Combustion characteristics of water-in-dodecane emulsion drops with various initial spacings were studied experimentally by using a free-falling drop burning apparatus. The initial drop spacings (Si) were 2.5, 5, 10, 40, 75 (70), 100. Si(s/di) was defined as the ratio of the drop center-to-center distance (s) to the initial drop diameter (di). The water content (β) and the oxygen concentration (ΩO2) were fixed at 5% and 21%, while two drop sizes 550 μm and 450 μm were compared. The results showed that the transition of the drop flame occurred for all cases in the experiment. For Si> 10 along the flow direction, the flame around the drops would change from a blue spherical flame to a yellow flame and a wake flame, and the drop flame extinguished later in the downstream region. Soot particles was generated and drops collision and merging occurred to form a flame tube for Si=2.5 in both cases of di= 550 μm and 450 μm. Besides, drop expansion was observed in both cases of di= 550 μm and di= 450 μm, while micro-explosion only occurred in the far downstream region for Si= 40, di= 450 μm. It was also shown that the emulsion drop evaporation rate was not a constant, and the trend of the drop evaporation rate was strongly influenced by changing the initial drop size.
|Publication status||Published - 2012|
|Event||12th International Conference on Liquid Atomization and Spray Systems, ICLASS 2012 - Heidelberg, Germany|
Duration: 2012 Sep 2 → 2012 Sep 6
|Conference||12th International Conference on Liquid Atomization and Spray Systems, ICLASS 2012|
|Period||12-09-02 → 12-09-06|
All Science Journal Classification (ASJC) codes
- Surfaces, Coatings and Films