الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The objective of this work is to assemble an object-oriented model of a VVER-1200 nuclear power plant including the reactor core, pressurizer, steam generator, and the secondary loop. Modeling was performed using Modelica language, which implies that each plant component would be made up of a system of Differential Algebraic Equations (DAEs). Modelica is a modeling language designed for the study of engineering system dynamics. One of its advantages is that it is declarative, focusing on what the model should describe, rather than how the model is solved. The related Thermopower Library as well as other libraries were used. The reactor coupled, non-linear core model is composed of three main sub-models, a reactor kinetics model, a fuel rod model, and a coolant channel model. The pressurizer was modeled according to the Bell and Åström 5 states‟ equations. The steam generator model was based on a heat exchange between a primary side which contains one-phase water, and a secondary side which contains two-phase water along the tube and finally 1-phase steam at the outlet. Following completion of the Primary Heat Transfer System (PHTS), it was connected to the balance of plant (BOP). Test and verification of all the developed models were performed. Then, the developed components were used to build a model called ALEX-IRIS which was used to model the IRIS reactor. Model predictions were compared with POLIMI simulators (Modelica, and Relap), as well as the IRIS design data. Good agreement was obtained. Then, VVER-1200 model (called ALX-VVER-1200) was constructed. Regardless of the protected intellectual property of the VVER-1200 NPP, it was still possible to produce an accurate collection of the necessary inputs, and verification results. The developed ALX-VVER-1200 model was used to generate the actual VVER-1200 design data under reactor nominal steady state conditions which was in good agreement. Then, the ALX-VVER-1200 model was used to analyze a Reactivity Initiated Accident (RIA) and the results were in good agreement with previous analysis utilizing ATHLET/BIPRVVER coupled system code from the literature. Finally, the developed model was used to predict the behavior of the plant dynamics in response to control rod step motion as well as coolant flow reduction. In each case, plant parameters like core total power, core inlet/outlet temperature and pressure as well as the steam generator power were predicted. In the future, the developed model can easily be used for safety related studies and building NPP training simulator with the aid of a suitable tools like LabVIEW. Ultimately, the model would also be used for control-oriented analysis to perform plant stability analysis, and design and synthesis of automatic control systems.