2014-11-28 
Lithuanian Energy Institute (202 a. Breslaujos st. 3, Kaunas, Lithuania) Author, Institution: Tadas Kaliatka, Lithuanian Energy Institute
Dissertation title: Study of the thermal hydraulic processes in Nuclear Fusion devices during Loss of Coolant event
Science area, field of science: Technological Sciences, Energetics and Power Engineering – 06T
Defense of the dissertation: 2014-11-28, 11:00, Lithuanian Energy Institute (Meeting Hall – AK-202 a.), Breslaujos st. 3, Kaunas, Lithuania.
Scientific Supervisor: Prof. Dr. Habil. Eugenijus UŠPURAS (Lithuanian Energy Institute, Technological Sciences, Energetics and Power Engineering – 06T)
Dissertation Defense Board of Energetics and Power Engineering Science Field
- Chairman – Prof. Dr. Habil. Stasys ŠINKŪNAS (Kaunas University of Technology, Technological Sciences, Energetics and Power Engineering – 06T);
- Prof. Dr. Habil. Juozas AUGUTIS (Vytautas Magnus University, Technological Sciences, Energetics and Power Engineering – 06T);
- Prof. Dr. Habil. Rimantas KAČIANAUSKAS (Vilnius Gediminas Technical University, Technological Sciences, Mechanical Engineering – 09T);
- Dr. Raimondas PABARČIUS (Lithuanian Energy Institute, Technological Sciences, Energetics and Power Engineering – 06T);
- Dr. Gediminas STANKŪNAS (Lithuanian Energy Institute, Technological Sciences, Energetics and Power Engineering – 06T).
Official Oponents:
- Prof. Dr. Gvidonas LABECKAS (Aleksandras Stulginskis University, Technological Sciences, Energetics and Power Engineering – 06T);
- Prof. Dr. Habil. Gintautas MILIAUSKAS (Kaunas University of Technology, Technological Sciences, Energetics and Power Engineering – 06T).
The doctoral dissertation is available at the libraries of Kaunas University of Technology (K. Donelaičio st. 20, Kaunas) and Lithuanian Energy Institute (Breslaujos st. 3, Kaunas).
Annotation:
One of the most potential future nuclear energy is the energy received from the collision of light nuclei – nuclear fusion energy. Several experimental devices around the world are already constructed or under construction. These experimental devices are designed in order to study the process occurring during energy generation in the nuclear fusion devices. The thermal hydraulic processes in cooling system of in-vessel components and vacuum vessel of nuclear fusion devices are not widely studied. Therefore, systematic and detailed experimental and numerical studies are important and relevant. In order to study the processes which occur in cooling systems of in-vessel components and vacuum vessels of nuclear fusion devices, the best estimate code RELAP5 was selected and numerical models were developed. For the validation of the models which represents the processes in the vacuum vessel the experimental data received from Ingress of Coolant Event experimental facility were used. The uncertainty and sensitivity analysis was provided for the calculation results of the ingress of water into vacuum vessel experiment. Using the experience gained from the modelling of Ingress of Coolant Event experiments, the numerical model of W7‑X experimental device was developed. Dealing with a complex analysis it was shown: the pressure increase rate in the vacuum vessel depends on the quantity of water ingress form the cooling system, processes in the vacuum vessel (evaporation due to pressure differences and the interaction with the hot surfaces) and steam condensation in the pressure increase protection system.