Model Selection for Predicting the Evaporation Rate of Aviation Fuels

The prediction of accurate evaporation rates for aviation fuels, which are complex mixtures of hundreds of hydrocarbon components with varying evaporation characteristics, remains a challenge. Multi-component vaporization models, such as distillation curve (DC) and diffusion limit (DL), are capable of predicting evaporation rates well but require the construction of surrogate fuels, which is difficult. Mono-component models, on the other hand, can be used for rapid evaporation conditions similar to those in a heat engine combustion chamber, with acceptable uncertainties. However, the accuracy of these models under engine-relevant operating conditions is unclear. This study aims to address this research gap by experimentally measuring the evaporation rates of two aviation fuels (TS-1 and Jet-A1) at different temperature conditions and evaluating the feasibility of current theoretical models for predicting evaporation rates under engine-relevant conditions. The study found that current models cannot accurately describe special events such as micro-explosions or slow evaporation, which were observed in the case of TS-1 droplets at temperatures above 823 K. This study highlights the need for more accurate models for predicting the evaporation rates of aviation fuels under engine-relevant conditions. © 2023 SAE International. All rights reserved.