Research Projects

Aviation fuels are generally liquid hydrocarbons with varying compositions of alkanes, iso-alkanes, cyclo-alkanes and aromatics. Modeling the combustion and emissions from practical systems using such fuels requires a fundamental understanding of the combustion reaction mechanism of these components, which is generally represented by a surrogate containing fewer hydrocarbons representative of the combustion properties. Reaction mechanisms and soot models of these surrogates are validated against experiments in canonical configurations of laminar flames like flat premixed flames or counterflow diffusion flames as these can be modelled as simpler one-dimensional systems by avoiding uncertainties pertaining to parameters other than combustion kinetics. Existing and upcoming legislations across many countries mandate the blending of sustainable aviation fuels (SAF) with traditional jet fuels as a step towards sustainability. Although made from sustainable resources and hence reducing the overall carbon footprint, these are still liquid hydrocarbon fuels which are meant to produce carbonaceous soot particles during combustion. Considering this, understanding the formation of soot from different types of SAF and establishing predictive capability for the same is imperative. Developing surrogates and their reaction mechanisms that could represent the combustion behavior and soot formation of different types of SAF would serve as a building block towards the combustion modeling of practical devices using these fuels. Although much has been explored for conventional jet fuels and the corresponding surrogate hydrocarbons, due to the upcoming nature of research pertaining to SAF, there is severe scarcity of experimental data pertaining to surrogates and corresponding to models for reaction mechanisms and soot. As a step towards addressing this, a set of experiments and development of numerical models are proposed. The experiments would involve measurement of temperature and soot volume fraction along with some important species like OH and aromatics during the combustion of some surrogate components of SAF in canonical flames. The measurements would be done on flat premixed flames and counterflow diffusion flames using existing laser diagnostics facilities at IIT Palakkad. The modeling would be done at IIT Delhi and would involve development of reduced reaction mechanisms for the said surrogate components coupled with a soot model based on hybrid method of moments. As research on SAF combustion and emissions is at a very nascent stage across the world, the experimental data from the project, and the reaction mechanisms hence developed would assist in predicting soot from SAF combustion in practical devices.