New doctoral dissertation

June 11, 2024
VILNIUS TECH Library invites you to follow the published new dissertations. The dissertation „Investigation of hydrodynamic and thermodynamic processes in the liquefied natural gas transportation and regasification system“ prepared by VILNIUS TECH, Vigailė Semaškaitė. The dissertation was prepared in 2019–2024. Supervisor – Prof. Dr Habil. Marijonas Bogdevičius.

The dissertation was defended at the public meeting of the Dissertation Defence Council of the Scientific Field of Transport Engineering in the SRA-I Hall of Vilnius Gediminas Technical University at 2 p.m. on 11 June 2024.

The research work concerns the current world energy situation, alternative fuels, specifically liquefied natural gas (LNG), and the minimisation of pollution, which is important in the transport sector. The technological analysis and theoretical investigations are applied to analyse hydrodynamic, thermo-dynamic and evaporation processes and determine hydraulic energy losses in LNG transportation and regasification systems, thereby increasing the technological availability of LNG terminals. The introduction presents the relevance of the research, its purpose, tasks, scientific novelty, and results obtained from theoretical research based on the technical parameters of the Floating Storage and Regasification Unit (FRSU) and the established technological regimes of the regasification process. It also specifies the significance of the dissertation’s topic, defensive statements, and a list of scientific publications published by the author. The first chapter analyses the transportation, storage and regasification technologies and challenges of LNG mathematical models. The chapter introduces LNG fundamentals, provides a global overview of the NG and LNG markets, and delves into transportation, storage, and regasification technologies, as well as mathematical models applied as technical solutions to evaluate technological problems. It focuses on the challenges associated with the thermal-physical properties of LNG that impact hydrodynamic and thermodynamic evaporation processes. The second chapter presents the analysis of FSRUs’ technical equipment and characteristics. It explains the estimation of LNG’s technical parameters and thermal-physical properties. The analysis aims to determine the technological parameters for creating theoretical mathematical models of LNG transportation and regasification systems. The third chapter considers mathematical models of the LNG transportation and regasification systems at an FSRU. The analysis of hydrodynamics, thermodynamics, and evaporation processes in the total LNG transportation and regasification systems was performed and adopted according to the researchers in this dissertation. Nine scientific articles focusing on the subject of the dissertation were published: three in scientific journals included in Clarivate Analytics Web of Science databases with IF; one in a scientific journal included in Elsevier Scopus databases with IF; one in Clarivate Analytics Web of Science Database Conference Proceedings; three in Elsevier Scopus Science Database Conference Proceedings; and two in peer-reviewed international conference materials.
 
Doctoral dissertation readers can search via VILNIUS TECH Virtual Library.

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