Spray combustion in engines

A few lecture hours and some pages of lecture notes are by far not sufficient to cover the broad subject of spray combustion in engines. As a matter of fact, dedicated journals and books exist on sprays. Therefore, the current lecture only serves as an introduction to the subject. Optimally, the lecture slides, text and references in this chapter should function as a "Quick Start Guide" to the vast literature on spray combustion in engines. The scope of this chapter is as follows. After an introductory section, we will look at different phenomena in fuel sprays (e.g., with what speed and angle they move, how they break up, evaporate and ultimately combust). After that we discuss different classes of spray models, ranging from simple measurement-based correlations to full CFD models (without going into details on the latter). In the section 8 some (semi-)phenomenological models are treated in more detail, since these provide a good balance between simplicity and physical insight. Since the text was written for a post-graduate combustion course, the level of this chapter is slightly more advanced than the rest of the lecture notes. Therefore, from the models discussed, only the Sandia model belongs to the core part of the Fuels & Lubes course.