Evaporation of a single ethanol droplet interacting with a premixed laminar CH4/air flame

Abstract

Among all phenomena occurring in liquid-fueled combustion chambers, one basic process is the interaction of droplets with the flame. Therefore, it is essential to understand the dynamics of an individual droplet interaction with a flame front in order to analyze more complex flames. The aim of this study is to investigate the evaporation of a single ethanol droplet interacting with a premixed laminar CH4/air flame. In the experimental part of the study, the droplet was injected into the stagnation flame. The visualization of the flame front and the temporal monitoring of the droplet evaporation were performed using optical technics (PIV, PTV, ILIDS). In the numerical part of the study, single droplet evaporation under constant temperature and stagnant environment was studied with the Eulerian-Lagrangian approach using the YALES2 solver. The variations of the droplet and gas properties were computed under N2 atmosphere and under flame conditions. From the vaporization rate calculations, it is observed that there is a slight effect of flame stretch due to the change in the temperature profile. It is also observed that the flame temperature has a dominant effect on the evaporation rate rather than the burnt gas composition.

Investigation of cellular instabilities and local extinction for two-phase flames under microgravity conditions

“…The evaporation of an isolated ethanol droplet was investigated previously under premixed methane/air flame conditions, and it is found that 50 µm diameter is high enough to cross the flame front under elevated temperatures, regardless of the gas composition [30]. Hence, the droplet passage through the flame field and its effects on the flame structure can properly be observed under the fixed conditions, reported in Table 2.…”

“…The schematic of the stagnation burner is given in Figure 2 (a). Details of the stagnation flame burner can also be found in other studies [30], [26]. Experimental configuration is represented in Figure 2 (b).…”