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Fuel element characterization
Halabuk, Dávid ; Suk, Ladislav (referee) ; Martinec, Jiří (advisor)
This bachelor thesis describes the fuel rods of VVER reactors. In addition to general description of fuel rod, there is also overview of the nuclear fuel used in the past and at present in Czech and Slovak nuclear power plants, as well as overview of the new trends in development of nuclear fuel. Big part of the thesis is focused on description of nuclear fuel and fuel cladding properties and the individual processes affecting fuel rod during fuel burnup. Next part describes in detail the causes of fuel failures occurring in VVER reactors. The last part of the thesis includes calculation of changes of deformations and stresses occurred in fuel cladding during pellet-cladding interaction. Calculation is done for four different shapes of fuel pellets and in addition to deformation and stress analysis, there are also calculated axial dilatations of fuel column and radial temperature distributions in fuel rod.
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Analysis of the Most Common Causes of Nuclear Fuel Failures During Operation
Ježek, Martin ; ČEZ,, Ondřej Zlámal, (referee) ; Katovský, Karel (advisor)
Nuclear fuel failures during the reactor operation happen quite often in the world. The theoretical part of this thesis is dedicated to the most common causes of nuclear fuel failures. It describes failure mechanism and corrective actions. The unfavorable trends in nuclear fuel behavior are prevented by suitable method of nuclear fuel monitoring. Some of them may affect the safety of the power plant. For example, the fuel assembly bow affects the function of rod cluster control assembly. Another part, which describes inspection methods, is devoted to inspection and repair of nuclear fuel. The thesis concentrates on the Temelin NPP, where there was implemented post-irradiation inspection program for checking compatibility between Westinghouse's fuel assemblies and water chemistry of reactor VVER. This program continues even after the change of nuclear fuel supplier. Practical part of this thesis is dedicated to proposal of a new method of fuel assembly bow measurement for Temelin NPP based on ultrasound. This proposal is supported by measurement on the experimental device for detection of spacer grid position developed by Research Centre Rez.
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Current Status of Nuclear Fuel Assemblies Inspections at Nuclear Power Plants World-Wide
Fendrychová, Michaela ; Temelín, Elektrárna (referee) ; Katovský, Karel (advisor)
This bachelor thesis deals with post irradiation examination (PIE) of spent nuclear fuel. The document briefly introduces basic light water reactor types (BWR, PWR, VVER) and construction of nuclear fuel for these reactors. Typical fuel failure types are described as well as methods for detection of such defects or failures. Consequently inspection methods suitable for commercial nuclear power plants are described. The primary goal of this thesis was to analyze existing inspection methods and to propose improvement of existing PIE at Temelín nuclear power plant. Therefore part of this thesis is devoted to description of fuel used at Temelín power plant, inspection methods currently applied at Temelín power plant and discussion of possible improvements of PIE.
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Current Status of Nuclear Fuel Assemblies Inspections at Nuclear Power Plants World-Wide
Fendrychová, Michaela ; Temelín, Elektrárna (referee) ; Katovský, Karel (advisor)
This bachelor thesis deals with post irradiation examination (PIE) of spent nuclear fuel. The document briefly introduces basic light water reactor types (BWR, PWR, VVER) and construction of nuclear fuel for these reactors. Typical fuel failure types are described as well as methods for detection of such defects or failures. Consequently inspection methods suitable for commercial nuclear power plants are described. The primary goal of this thesis was to analyze existing inspection methods and to propose improvement of existing PIE at Temelín nuclear power plant. Therefore part of this thesis is devoted to description of fuel used at Temelín power plant, inspection methods currently applied at Temelín power plant and discussion of possible improvements of PIE.
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Analysis of the Most Common Causes of Nuclear Fuel Failures During Operation
Ježek, Martin ; ČEZ,, Ondřej Zlámal, (referee) ; Katovský, Karel (advisor)
Nuclear fuel failures during the reactor operation happen quite often in the world. The theoretical part of this thesis is dedicated to the most common causes of nuclear fuel failures. It describes failure mechanism and corrective actions. The unfavorable trends in nuclear fuel behavior are prevented by suitable method of nuclear fuel monitoring. Some of them may affect the safety of the power plant. For example, the fuel assembly bow affects the function of rod cluster control assembly. Another part, which describes inspection methods, is devoted to inspection and repair of nuclear fuel. The thesis concentrates on the Temelin NPP, where there was implemented post-irradiation inspection program for checking compatibility between Westinghouse's fuel assemblies and water chemistry of reactor VVER. This program continues even after the change of nuclear fuel supplier. Practical part of this thesis is dedicated to proposal of a new method of fuel assembly bow measurement for Temelin NPP based on ultrasound. This proposal is supported by measurement on the experimental device for detection of spacer grid position developed by Research Centre Rez.
|
|
|
Fuel element characterization
Halabuk, Dávid ; Suk, Ladislav (referee) ; Martinec, Jiří (advisor)
This bachelor thesis describes the fuel rods of VVER reactors. In addition to general description of fuel rod, there is also overview of the nuclear fuel used in the past and at present in Czech and Slovak nuclear power plants, as well as overview of the new trends in development of nuclear fuel. Big part of the thesis is focused on description of nuclear fuel and fuel cladding properties and the individual processes affecting fuel rod during fuel burnup. Next part describes in detail the causes of fuel failures occurring in VVER reactors. The last part of the thesis includes calculation of changes of deformations and stresses occurred in fuel cladding during pellet-cladding interaction. Calculation is done for four different shapes of fuel pellets and in addition to deformation and stress analysis, there are also calculated axial dilatations of fuel column and radial temperature distributions in fuel rod.
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