The Diploma thesis on the topic of Increased performance turbomachinery in EDU the NPR changing describes in detail some important devices of technology system of the secondary circuit of Dukovany Nuclear Power Plant together with their task in the thermal circulation. There is a computational model of secondary circuit according to the present thermal schema created in the main part of the thesis. At the end of the thesis, the possibilities of the increase of the terminal power of turbomachinery, specifically of the turbogenerator, by the exhange of low-pressure heaters (NPR) are stated. Obtained results are documented by drawings of the thermal schemes.

The main aim of this diploma thesis is to acquaint the reader by the means of research with heat diagrams of nuclear power plants, and subsequently, submit a scheme design of partial components and their involvement to heat diagram. The work also reflects different drive variations of circulation pumps and cooling circuits.

La conservation du circuit secondaire des réacteurs à eau sous pression pendant les périodes d’arrêts nécessite la mise en oeuvre de conditions spécifiques afin de limiter les phénomènes de corrosion des aciers au carbone, qui composent en grande majorité ce circuit. Les méthodes de conservation impliquent une mise en oeuvre contraignante et couteuse lors des arrêts de tranche. L’injection d’amines filmantes (AF), en fonctionnement avant les phases d’arrêt, constitue une voie d’étude intéressante afin de protéger les composants en acier au carbone tout en simplifiant la mise en oeuvre de la conservation à l’arrêt. Le but de ce travail de thèse est d’étudier le comportement et l’efficacité d’une AF pour la protection des aciers au carbone dans les conditions représentatives des centrales REP. Pour mener à bien ces travaux, la spectroscopie d’impédance électrochimique a été utilisée en appui à des observations de surface par microscopie optique et microscopie électronique à balayage et à des analyses de surface par spectroscopie de photoelectrons X. Tout d’abord, des films d’AF formés sur un acier au carbone à basse température (80 °C) dans des conditions de dépôts optimisées ont été caractérisés (épaisseur, permittivité) et leurs propriétés inhibitrices de corrosion évaluées en milieu Na2SO4 à pH proche de 10. Cette première étude a permis de valider une méthode de caractérisation des films à travers l’analyse des données d’impédance à haute fréquence. Puis, cette méthode a été utilisée pour suivre et caractériser la formation de films d’AF d’une part, sur de la magnétite électrodéposée dans les conditions de dépôt optimisées, et d’autre part, sur des coupons d’acier au carbone polis dans les conditions thermo-chimiques du circuit secondaire à 120 °C, 220 °C et 275 °C en fixant la concentration en AF en solution à 2 ppm. Les suivis par impédance au cours du temps de l’acier au carbone traité avec l’AF ont permis de tester l’efficacité des films pendant une phase de conservation humide. Les résultats mettent en évidence l’influence des conditions de formation des films d’AF (température, concentration en AF, temps de traitement et nature du substrat) sur leur efficacité contre la corrosion en conservation. D’après nos résultats, seul le traitement réalisé à 120 °C a abouti à la formation d’un film d’AF pour lequel la protection de l’acier au carbone a été confirmé à l’issu d’une conservation humide de 30 jours. Les films formés sur l’acier au carbone nu à basse température ont montré une forte susceptibilité à la désorption au cours du temps, de même que pour les films d’AF déposés à 220 °C, et ce même avec une forte concentration en AF de 25 ppm. Enfin, pour les dépôts effectués à 275 °C, la cause la plus probable de la diminution de l’efficacité contre la corrosion observée entre 2 h et 24 h de traitement viendrait de la dégradation thermique de l’AF, détectée en solution au-delà de 2 h d’exposition à cette température. / The preservation of the secondary circuit of pressurized water reactors during layup periods requires the implementation of specific conditions in order to limit the corrosion phenomena of carbon steels, which constitute the major part of this circuit. These conservation methods are costly and very demanding for the operating. The injection of film-forming amines (FFA), in operation in before shutdown phases, is an interesting route of study to protect carbon steel components while simplifying the conservations. The aim of this thesis work is to study the behavior and the efficiency of an FFA for the protection of carbon steels in the representative conditions of PWRs. To carry out this work, electrochemical impedance spectroscopy was used with surface observations by optical microscopy and scanning electron microscopy and surface analysis by X-ray photoelectron spectroscopy. First, FFA films formed on a carbon steel at low temperature (80 ° C) under optimized deposition conditions were characterized (thickness and permittivity) and their corrosion inhibiting properties evaluated in an Na2SO4 medium at pH close to 10. This study allowed to validate a method for the film characterization through the analysis of the high frequency part of the impedance data. Then, this method was used to follow and characterize the FFA film formation on electrodeposited magnetite in optimized deposition conditions in one hand, and on a carbon steel under the thermo-chemical conditions of the secondary circuit at 120 °C, 220 ° C and 275 °C using FFA concentrations fixed at 2 ppm on the other hand. Impedance monitoring over time of the FFA-treated carbon steel allowed the effectiveness of the films to be followed during humid conservation. The results highlight the influence of FFA film formation conditions (temperature, FFA concentration, treatment time and nature of the substrate) on their efficiency against corrosion during conservation. According to our results, only the treatment at 120 °C resulted in the formation of an FFA film that could protect the carbon steel from corrosion in humid conservation during 30 days. The films formed on bare carbon steel at low temperature showed a high susceptibility to desorption over time, as well as for FFA films deposited at 220 °C, even with a high FFA concentration of 25 ppm. Finally, for FFA deposition made at 275 °C, the decrease of the efficiency against corrosion observed over time would come from the thermal degradation of the FFA, detected in solution beyond 2 hours of exposure to this temperature.

The main aim of this thesis is the model design and control the secondary circuit block VVER 440. The search part of my work is a description of the secondary circuit. In the first part of the calculation is performed for the rated secondary circuit. The second calculation part focuses on the calculation circuit of the secondary for the reduced, influenced by shutting down one steam generator.

The aim of this thesis is to create a conceptual design of the secondary and tertiary circuit of a new nuclear power plant in our country, which is preceded by a brief search of particular generations of nuclear reactors. The VVER-1200 reactor became the model for the new nuclear power plant. There was designed a heat diagram containing primary components in this work. After that, there was the balance calculation and calculation of parameters of the main devices of the proposed scheme such as condenser, low-pressure and high-pressure regeneration exchangers and steam generator.

The thesis is mainly focused on the design of the intermediate heat exchanger primary circuit of the reactor ESFR. Heat exchanger is calculated heat, hydraulic and strength and is finally processed part drawings. There are designed the basic dimensions of the tube bundle and container heat exchanger. There are included an overview of concepts and so far used types IHX at the nuclear power plants with fast reactors. There are also mentioned basic parameters of the project ESFR and evaluated the safety and operational reliability of the heat exchanger.

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This diploma thesis deals with various ways of energetically advantageous utilization of waste heat produced by industrial technologies. The focus of the diploma thesis is both to provide an overview of different ways and places of origin of waste heat in industrial technologies and of its possible reutilization, to suggest a concrete air heating system using waste heat and to propose a long-distance hot water pipe which supplies hot water pipe system with energy. First, technologies producing waste heat and some ways of regressing of heat in such technologies are theoretically described. Second, the equipment for transferring of heat and for adjustment of thermal energy parameters is described. A special focus is put on water supplies of the Nuclear Power Plant Dukovany and some selected parts of its secondary circuit, which is waste heat collected from. The analysis is supplemented by a calculation of theoretical quantity of waste heat. The aim of the calculation is to determine whether waste heat can be a source of energy for heating. Then, a current system of heating of three selected buildings in the area of the Nuclear Power Plant Dukovany is briefly described. Based on the gained knowledge, a project of air heating with two heat pumps type water – water, a heat receiver preparing warm service water and three recuperative units for preheating of fresh heating air is designed. The selection of main parts of the air heating is amended by a calculation of purchase costs and electric energy consumption. After that, the focus is placed on choice of type of hot water pipe – its trace is stated and an indicative estimation and a thermal-conditions calculation in the hot water pipe are made. The preliminary calculation serves as a source of information for a final project of air heating and calculation of changes of temperatures longwise the hot water pipe. The project contains also a calculation of pressure losses and an analysis of economical questions concerning hot water pipes. In conclusion, the results of project of air heating and hot water pipes are summarized.

Thesis focuses on a detailed technical description of all important parts of secondary circuit in Dukovany power plant and its connection to other systems of power plant. In thesis are analyzed significant adjustments which have been made during the entire operation of power plant including in particular the actions associated with project called Utilization of project reserves of units EDU. In the main part of the thesis were carried out calculations of the power plant's power for states before and after the modernization and there is also analyzed the impact of individual changes on the whole power plant. These changes are with the entire secondary circuit drawn in the T-s diagram.