Puffing/micro-explosion in droplets of rapeseed oil with coal micro-particles and water

The results of experimental investigation and modelling of puffing/micro-explosion in composite (rapeseed oil mixed with coal micro-particles and water) droplets are described. The modelling is based on the previously developed model of the process, using the assumption that a spherical water subdroplet is located in the centre of a fuel droplet. Predicted and observed times to puffing/micro-explosion decreased with increasing ambient gas temperatures and mass fractions of micro-particles in rapeseed oil (up to 60%). The maximal deviations between the experimental and modelling results were observed for ambient gas temperature 850 K and mass fraction of micro-particles in oil 60%. This is linked to the fact that, for large mass fractions of coal and low ambient gas temperatures, bubbles can be initiated at the coal micro-particles. This effect is not considered in the model.

Automated summary

This paper describes the results of experimental investigation and modeling of puffing/micro-explosion in composite droplets of rapeseed oil mixed with coal micro-particles and water. The modeling is based on a previously developed model, which assumes the presence of a spherical water subdroplet in the center of a fuel droplet. The predicted and observed times to puffing/micro-explosion decreased as the ambient gas temperatures and mass fractions of micro-particles in rapeseed oil increased.