Multi-component vaporisation: Tabulated distillation curve models for ideal atmospheric-pressure conditions

Multi-component vaporisation of liquid fuels in combustion processes is typically described using simplified approaches for computing time reasons. Existing approaches include surrogate, continuous thermodynamics, quasi-discrete component and distillation curve models. These approaches, however, strongly simplify composition and physical properties and hence the vaporisation behaviour when applied to technical fuels with numerous species from different chemical classes. Therefore, this study developed a new approach for an accurate and efficient mathematical description of single-droplet vaporisation of complex technical fuels. This approach utilises the link between distillation and vaporisation, assumes rapid internal mixing and isobaric conditions and employs tabulated distillation curve models. These models are based on tabulated equilibrium distillation and physical property curves and have thus a theoretical basis in contrast to previous distillation curve models. In this study, tabulated distillation curve models are presented for a pure liquid compound, a bi-component liquid and a liquid technical fuel assuming ideal atmospheric-pressure conditions. ... mehrIn addition, single-droplet vaporisation predictions based on these models are compared with predictions based on discrete component models. The comparisons show that tabulated distillation curve models can describe the vaporisation of multi-component liquids under ideal conditions with similar accuracy as discrete component models when using the same physical property models. The predictions also highlight an often overlooked aspect that the development of vaporisation models for technical fuels has to be assisted with the generation of appropriate physical property data. Furthermore, the single-droplet vaporisation simulations suggest that, for any multi-component liquid, tabulated distillation curve models require similar computing times as discrete component models with eight components.