3D-CFD analysis of a high performance hydrogen fuelled engine

• Autor(a) principal: Ferreira, João Eduardo Mota
• Data de Publicação: 2022
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10773/34366
• topic: Internal combustion engine; Hydrogen; Direct injection computational fluid dynamics; Lean mixture; NOx emissions

Regarding carbon dioxide emissions, they would not be a problem on an internal combustion engine fuelled with hydrogen, since there is no carbon in the combustion reactants. Besides, the combustion properties of hydrogen are highly promising. However, the conversion of a gasoline engine to be run on hydrogen is not direct, due to technological concerns derived from hydrogen particularities. Furthermore, nitrogen oxides are still part of the reaction by-products, although their production can be controlled depending on factors as equivalence ratio and the top temperature achieved inside the combustion chamber. This work aimed at performing three-dimensional computational fluid dynamics analysis of a cylinder unit of a recent production high-performance gasoline direct injection engine, although fuelled with hydrogen. Literature review allowed to find the strengths and weaknesses of several strategies. Once direct injection of hydrogen was selected as a must-have, simulations with two different overall lean mixtures, across a range of spark timings, provided trends of performance and emissions. Still, due to the requirement of high power output of the high-performance engine, these were not ultra-lean emission-free mixtures, for which also all sorts of abnormal combustion events would be avoided. By analysing the simulation results, subsequent study directions can be established, being water injection into the cylinder and mixture formation improvement the follow-up steps to implement...