S. Breidokaitė “Modeling of the neutron transport based on the Monte Carlo method and the numerical estimation of radiological quantities towards the future nuclear fusion reactor DEMO” doctoral dissertation defence

Author, Institution: Simona Breidokaitė, Lithuanian Energy Institute

Science area, field of science: Technological Sciences, Energetics and Power Engineering, T006

Scientific Supervisor: Chief Researcher Dr. Gediminas Stankūnas (Lithuanian Energy Institute, Technological Sciences, Energetics and Power Engineering, T006)

Dissertation Defence Board of Energetics and Power Engineering Science Field:
Chief Researcher Dr. Viktorija Grigaitienė (Lithuanian Energy Institute, Technological Sciences, Energetics and Power Engineering, T006) – chairperson
Chief Researcher Dr. Ričardas Krikštolaitis  (Vytautas Magnus University, Technological Sciences, Energetics and Power Engineering, T006)
Assoc. Prof. Dr. Wojciech Krolas (The Henryk Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, Poland, Technological Sciences, Energetics and Power Engineering, T 006)
Prof. Dr. Giedrius Laukaitis (Kaunas University of Technology, Technological Sciences, Materials Engineering, T008)
Chief Researcher Artūras Plukis (State research institute Center for Physical Sciences and Technology, Natural Sciences, Physics, N 002)

Dissertation defence meeting will be at the conference room at Lithuanian Energy Institute (Breslaujos 3 – 202, Kaunas)

The doctoral dissertation is available at the library of Kaunas University of Technology (Gedimino 50, Kaunas) and on the internet: S. Breidokaitė el. dissertation.pdf

© S. Breidokaitė, 2025 “The text of the thesis may not be copied, distributed, published, made public, including by making it publicly available on computer networks (Internet), reproduced in any form or by any means, including, but not limited to, electronic, mechanical or other means. Pursuant to Article 25(1) of the Law on Copyright and Related Rights of the Republic of Lithuania, a person with a disability who has difficulties in reading a document of a thesis published on the Internet, and insofar as this is justified by a particular disability, shall request that the document be made available in an alternative form by e-mail to doktorantura@ktu.lt.”

Annotation: This dissertation presents a detailed analysis of neutron transport and radiological characteristics in key components of the future EU DEMO fusion reactor, specifically the divertor, vacuum vessel, and breeding blanket. The study is based on the Monte Carlo method combined with advanced geometric models and updated nuclear reaction databases, allowing for precise evaluation of neutron interactions with structural and functional materials. Detailed modeling of radionuclide formation mechanisms, activity, decay heat, dose rate, and their spatial distributions was carried out, taking into account the planned operational conditions of the EU DEMO reactor. The work compares two main breeding blanket concepts to determine their influence on neutron distribution and other radiological parameters. Special emphasis is given to the long-term behavior of materials, including radionuclide generation and radioactive waste management issues, which are critical for reactor safety and environmental protection. Additionally, the study evaluates neutron transport characteristics across different reactor component layers, enabling a deeper understanding of the spatial distribution of radiological processes within the reactor geometry. The results of this work can support the optimization of material selection and design decisions aimed at reducing radiological loads and facilitating the management of radioactive waste in fusion reactors.