A theoretical study of quasisteady sphericosymmetric combustion of alcohol droplets

A distinct characteristic of alcohol droplet combustion is absorption of moisture, generated as combustion product, during early part of the droplet life. A theoretical model for combustion of alcohol droplets has been developed. The quasisteady sphericosymmetric gas phase equations have been solved analytically while the transient diffusive liquid phase equations have been solved numerically. It is observed that neglecting the effect of moisture absorption in combustion modelling leads to underprediction of droplet life and overprediction of flame temperature and flame stand-off ratio. The results show that for alcohols with boiling points lower than that of water, a significant amount of moisture, generated during combustion is absorbed by the droplet. Absorption of this moisture prolongs droplet life and reduces flame temperature. A similar effect is also observed with increasing initial moisture content in the droplet.