|
Orbital welding in terms of nuclear power plant Temelin
Toman, Petr ; Šnajdárek, Ladislav (referee) ; Fiedler, Jan (advisor)
The bachelor thesis deals with the selection of a suitable system for Orbital welding of impulse pipe at the Temelín Nuclear Power Plant. The aim of this work is to describe the current TIG method of manual welding, to describe the available Orbital welding technology, to select a suitable type of kit and to design an experiment to compare the products of individual manufacturers.
|
|
The concept for passive cooling of the VVER-1000 reactor
Lamoš, Pavel ; Suk, Ladislav (referee) ; Martinec, Jiří (advisor)
This thesis is focused on the design of passive cooling system for a nuclear reactor VVER- 1000.This type of reactor is located in the Czech Republic in the location of Nuclear power plant Temelín. The thesis states an overview of the different cooling systems of nuclear power plants. The thesis is focused on passive safety system especially on passive cooling system, so there was done an overview of currently used passive safety system. In the work is discussed nuclear safety and the maximum projected accident of VVER-1000, which is called LOCA accident. In the design part of the thesis was done thermal calculation of heat exchangers. Exchangers are designed as condensers with a natural flow, where cooling of system is provided by outside airflow in case an accident. The results are evaluated at the end of the thesis.
|
|
Renewal of hermetic pipe penetrations
Kratochvíl, Zdeněk ; Chladil, Josef (referee) ; Kalivoda, Milan (advisor)
The topic of this work is the renewal of hermetic pipe penetrations within the primary loop of a nuclear power station. A description of the Dukovany nuclear power plant is included at the beginning, ranging from basic description to details of the renewed component and the reasoning for its replacement. Following is a description of the technologies, which are applied in order to restore the hermetic pipes, the choice of the placement of the heterogeneous weld and the compilation of a workflow for the renewal in the environment of the primary loop while maintaining the quality standards and the strict safety conditions. The conclusion includes a calculation of the expenses tied with the chosen variant the reasoning behind the renewal regarding the length of the outage.
|
|
The Nuclear Power Plant – The Green Source of Energy
Hynčica, Martin ; Vágner, Jiří (referee) ; Vágner, Jiří (referee) ; Matal, Oldřich (advisor)
This diploma thesis deals with nuclear energetics and its impact to the environment. Present state of the energetics, mainly nuclear energetics, in the Czech Republic is discussed here. Also perspective of nuclear energetics is given. The thesis describes nuclear power plant waste handling and also spent nuclear fuel handling. Nuclear power plant is compared with other sources of electric energy, which are counted to the energetic mix. The author focuses on fossil fuels and also on the renewable energy sources. The amount of produced waste to the unit of produced energy, built up area, safety and economic indicators and other parameters are followed for each source of energy.
|
| |
|
Liquid discharges of 14C in the Czech nuclear power plants and estimation of their radiological impacts
Chvátalová, Barbora ; Kotlík, Josef (referee) ; Čáslavský, Josef (advisor)
This thesis deals with the determination of 14C activity in liquid discharges from the Czech nuclear power plants and with the estimation of their radiological impacts on the vicinity of nuclear power plants. This work summarizes the issue of 14C liquid discharges of several nuclear power plants in the world and Czech nuclear power plants are compared to them. The sewage routs of liquid discharges from control tanks to waste water station are described in this thesis for both power plants - Dukovany and Temelín. Measured values of the 14C activity in liquid discharges from nuclear power plants Temelín and Dukovany are presented in this work. The procedure for calculating the exposure of representative persons as a result of liquid discharge of 14C activity is described in this thesis. The resulting values of annual commited effective dose for each age category of representative persons are presented in this work.
|
|
Facelift PDU
Rokotianskaia, Kseniia ; Dvořák, Tomáš (referee) ; Nový, Alois (advisor)
The subject of the diploma thesis is the elaboration of an architectural study of the reconstruction of the pre-plant zone of the Facelift of the Dukovany power plant. The construction site is an area that belongs to the village of Dukovany and borders the village of Rouchovany. As a whole, this area is in poor technical and architectural condition. However, its location gives potential for new uses. The solved area belongs to the ČEZ nuclear power plant.
|
|
Formulation the Methodology for Analysis the Seismic Response of the Piping Systems with Viscose Dampers
Chlud, Michal ; Salajka, Vlastislav (referee) ; Kanický, Viktor (referee) ; Malenovský, Eduard (advisor)
Viscous dampers are widely used to ensure seismic resistance of pipelines and equipment in nuclear power plants. Damping characteristics of these dampers are nonlinearly frequency dependent and thus causing complications in computational modelling of seismic response. Engineers commonly use two ways to deal with this nonlinearity: The first option is to consider damper by means of “snubber”. This is essentially linear spring element that is active for dynamic load and does not resist static loads. Snubber behaviour during seismic event is described by a equivalent stiffness (sometimes called pseudostiffness). The equivalent stiffness could be defined by the iterative calculations of piping natural frequencies and mode shapes taking into account seismic excitation. However, in complicated structures such as the main circulation loop of nuclear power plant the iterative calculation is difficult and could bring significant inaccuracies. On the other hand, the benefit of such modelling is a possibility to apply the commonly used linear response spectrum method for a solution. The second option is to describe damping characteristics using suitable rheological model. The seismic response is than determined by direct integration of the equations of motion. The behaviour of dampers is described exactly enough but the calculation and post-processing, especially nodal stresses time-histories, are time consuming. The goal of this work was to find a methodology for determining the seismic response of complex pipe systems with viscous dampers. Methodology allows a sufficiently accurate determination of the seismic response of piping systems and also allows obtaining of the results in effective time. The procedure is as follows. Firstly, specialized piping program (AutoPIPE) is used for the development of computational model. Next step is to determine a static response of structure and its verification with experimental measurements, if possible. Using script in Python language a computational model is converted from AutoPIPE into general finite element model in ANSYS system. Four-parameter Maxwell rheological model is used to describe behaviour of viscous dampers. Seismic load is represented by synthetic accelerograms. Newmark algorithm of direct integration of the equation of motion is used to obtain seismic response (only reactions and displacements in nodes of interest are necessary). Than is the equivalent stiffness is than gained from displacements and reactions as median value of their ratios. Received stiffness are subsequently transferred to AutoPIPE program where the seismic solution is performed using response spectra method. Finally, the dynamic response is combined with the static response and stress assessment according standards is done. The created methodology was applied in the seismic resistance calculation of the main circulation piping and piping of pressurizer in nuclear power plants type VVER 440 and type VVER 1000.
|
|
Temperature measurement in reactor VVER 440
Virgl, Martin ; Katovský, Karel (referee) ; Povalač, Aleš (advisor)
The main goal of this work is to get acquainted with the issues of temperature measurement and signal digitization in the theoretical level and temperature measurement in the VVER 440 reactor and on inseparable parts of the main circulation loops of the Dukovany Nuclear Power Plant and signal processing of temperature sensors. The measurement of temperatures in the power plant reactor is focused mainly on the used temperature sensors, A / D converters and a description of the systems processing these outputs. Furthermore, the work analyzes the data obtained during the calibration of temperature sensors in the isothermal state and the measurement of the resistance thermometer and thermocouple in laboratory conditions.
|
|
Effect of a nuclear power plant in terms of radiatin burden
Vániš, Jiří ; Procházka, Zdeněk (referee) ; Belatka, Martin (advisor)
This text deals with ionizing radiation affecting nuclear power plant personnel and surrounding population. Irradiation limits of radiological industry personnel are also mentioned along with ways of protecting them and checks on absorbed ionizing radiation dose. In conclusion, a nuclear power plant, as a source of ionizing radiation, and its effects on contamination of water sources and gas vents are evaluated. The next part be engaged problematical of storage nuclear waste from the time, when is removed the nuclear waste from nuclear reactor, trough permanent storage.
|