Public defence in mechanical engineering Yuri Kroyan M.Sc. (Tech)
Opponent Professor Öivind Andersson, Lund University, Sweden
Custos Professor Martti Larmi, Aalto University, School of Engineering, Department of Mechanical Engineering
Mitigation of climate change is not possible by means of one technology solely. Fuel and electricity power mobility around the world and both could be produced from renewable or fossil raw materials. Renewable fuels have a significant potential to reduce greenhouse gas emissions of most passenger vehicles and aircraft jet engines. However, it is important to carefully assess their impact on end-use sectors to ensure effective decarbonization and facilitate their market commercialization. The present dissertation studies the performance of alternative fuel candidates in the transport sector and highlights challenges toward their successful market uptake. Specific attention is paid to fuel properties and their impact on fuel economy. Relying on literature data, three mathematical models were developed for fuel consumption estimations using fuel properties exclusively. The targeted sectors are a regular fleet of spark-ignition light-duty vehicles, flex-fuel vehicles, and aircraft jet engines. The density and calorific content appeared in all developed models among the most important fuel properties. However, in the case of on-road transport also properties showing resistance to knocking combustion turned out to be significant along with oxygen content and vapor pressure. In the case of the jet model, additionally, viscosity played an important role. It has been observed that although some alternative fuels might increase volumetric fuel consumption (such as ethanol, methanol, butanol, or synthetic paraffinic kerosene), they tend to reduce their energy consumption and carbon dioxide emissions. The developed models could be applied to estimate the end-use performance of alternative liquid fuels (from single chemical compounds to multimolecular fuels). This in turn might support the development of new fuels dedicated to the transport sector, by providing an early insight into their performance and emissions in relevant end-use applications.