Deehan, Timothy;
(2023)
Investigating the combustion and emission characteristics of lignocellulosic derived future fuels with novel chemical reactivity in a heavy-duty compression ignition engine.
Doctoral thesis (Ph.D), UCL (University College London).
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Abstract
It is indisputable that anthropogenic climate change has severely impacted the global environment. The continual growth in greenhouse gas emissions since the industrial revolution has increased the global average temperature, disrupted weather patterns and will soon turn habited parts of the world inhospitable to human life. A vital step in lowering net CO2 emissions as the global economy transitions away from fossil fuels is increasing the role of biofuels as a CO2 neutral source of hydrocarbon fuel. This work presents experimental studies on the impact of molecular structure on combustive characteristics and emissions in a heavy-duty compression ignition engine, representative of engines in difficult to decarbonise sectors. Modifications to the engine allowed for direct measurements on the process of combustion, whilst exhaust gases and particulates were measured in real time. Four series of engine tests were carried out under constant injection duration and timing. Each focused on a specific subset of potential future fuels, such that direct comparisons between combustion performance would provide insight into; novel chemical reaction pathways, novel bio-derivable chemical structures, widening the pool of waste-based biofuel feedstocks or the considerations needed when designing future fuels. In tests on methyl nonanoate esters, the inclusion of a Michael Acceptors (α, β-unsaturated carbonyls) was found to reduce the duration of ignition delay. Tests on lactone isomerism found ring-size to have greater influence on ignition delay than alkyl chain length. Date pit methyl esters were found to exhibit similar combustive characteristics and emissions to rapeseed methyl esters, improving the outlook for adoption of additional waste-based feedstocks. The etherification of an alcohol derived from lignocellulosic biomass significantly reduced the duration of ignition delay in test fuels blends even at a low 3.5 % conversion yield.
| Type: | Thesis (Doctoral) |
|---|---|
| Qualification: | Ph.D |
| Title: | Investigating the combustion and emission characteristics of lignocellulosic derived future fuels with novel chemical reactivity in a heavy-duty compression ignition engine |
| Open access status: | An open access version is available from UCL Discovery |
| Language: | English |
| Additional information: | Copyright © The Author 2023. Original content in this thesis is licensed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) Licence (https://creativecommons.org/licenses/by-nc/4.0/). Any third-party copyright material present remains the property of its respective owner(s) and is licensed under its existing terms. Access may initially be restricted at the author’s request. |
| Keywords: | Biofuels, Engines, Heavy-duty compression ignition, Biofuel synthesis, Biofuel identification, Biofuel combustion |
| UCL classification: | UCL UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science > Dept of Mechanical Engineering |
| URI: | https://discovery-pp.ucl.ac.uk/id/eprint/10173630 |
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