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dc.contributor.advisorSarkisov, Lev
dc.contributor.advisorDuren, Tina
dc.contributor.authorHarrison, Alexander James
dc.date.accessioned2017-02-22T15:08:04Z
dc.date.available2017-02-22T15:08:04Z
dc.date.issued2016-06-27
dc.identifier.urihttp://hdl.handle.net/1842/20399
dc.description.abstractCarbonaceous deposits accumulate on the majority of the inner surfaces of internal combustion engines. The presence of these deposits is known to cause impaired engine performance. This is manifested as increased knocking, higher fuel consumption, higher emissions and other adverse effects. One of the proposed mechanisms for this behaviour is the adsorption and desorption of fuel components in the pores within the deposit. The porous nature of the deposits promotes this behaviour, altering the fuel composition and reducing the amount of fuel entering the combustion chamber. Previous research in this area was aimed at determining the porous structure of the deposits by combining experimental procedures with molecular simulations to investigate adsorption interactions with fuel components. Using a characterisation procedure regularly applied to activated carbons, a molecular model was developed that was able to provide new insights into the deposit structure. This model enabled predictions to be made for the single-component adsorption of normal heptane and iso-octane, two species commonly used as a gasoline reference fuel. Results showed significant adsorption of both species, and highlighted the impact of adsorption into the internal porous structure of the engine deposits. The aim of this thesis is to further investigate adsorption in engine deposits by expanding the studies to more complex systems. We develop a model to predict the adsorption of normal heptane, iso-octane, toluene and their mixtures in deposits of different origins and under different conditions. The study of multi-component mixtures provides insight into selectivity effects of adsorption under confinement, while at the same time bringing the systems under consideration closer to realistic multi-component mixtures that better represent fuel blends. The study also considers for the first time adsorption of aromatic species, both as a single component and in mixtures, since aromatics have a high presence in gasoline fuel. We explore the influence of molecular structure of adsorbing species, composition of the bulk mixture and temperature on the uptake and selectivity behaviour of the engine deposits. We demonstrate that under equilibrium conditions, deposits can adsorb substantial amounts of hydrocarbon species of all types. However, selectivity behaviour in engine deposits was found to be a subtle and complex property, highly sensitive to both pore size and system pressure.en
dc.contributor.sponsorotheren
dc.language.isoenen
dc.publisherThe University of Edinburghen
dc.relation.hasversionA. J. Harrison, R. F. Cracknell, J. Krueger-Venus, and L. Sarkisov. “Branched versus linear alkane adsorption in carbonaceous slit pores” Adsorption, 20(2- 3):427-437 (2014)en
dc.relation.hasversionA. J. Harrison, R. F. Cracknell, J. Krueger-Venus, and L. Sarkisov. “Computer Simulation Studies of Adsorption of Binary and Ternary Mixtures of Gasoline Components in Engine Deposits" SAE Int. J. Fuels Lubr., 7(3):756-761 (2014)en
dc.relation.hasversionL. Sarkisov and A. J. Harrison “Computational structure characterisation tools in application to ordered and disordered porous materials” Molecular Simulation, 37(15):1248-1257 (2011)en
dc.subjectengine depositsen
dc.subjectfuel componentsen
dc.subjectadsorptionen
dc.subjectfuel compositionen
dc.subjectactivated carbonsen
dc.subjectheptaneen
dc.subjectiso-octaneen
dc.subjectgasolineen
dc.subjectinternal porous structureen
dc.titleMolecular simulation studies of adsorption of fuel components and their mixtures in engine depositsen
dc.typeThesis or Dissertationen
dc.type.qualificationlevelDoctoralen
dc.type.qualificationnamePhD Doctor of Philosophyen


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