Models for automotive fuel droplets heating and evaporation

The paper presents recent approaches to the modelling of heating and evaporation of automotive fuel droplets with application to biodiesel, diesel, gasoline, and blended fuels in conditions representative of internal combustion engines. The evolutions of droplet radii and temperatures for gasoline, diesel, and a broad range of biodiesel fuels and their selective diesel fuel blends have been predicted using the Discrete Component model (DCM). These mixtures combine up to 112 components of hydrocarbons and methyl esters. The results are compared with the predictions of the case when blended diesel-biodiesel fuel are represented by pure fossil and biodiesel fuels. In contrast to previous studies, it is shown that droplet evaporation time and surface temperature predicted for 100% biodiesel (B100) are not always close to those predicted for pure diesel fuel. Also, the previously introduced MultiDimensional Quasi-Discrete model and its application to these fuels and their mixtures are discussed. The previous application of this model has resulted in up to 96% reduction in CPU time compared to the case when all fuel components are considered using the DCM.