Sökning: "Kärnenergiteknik"

Visar resultat 1 - 5 av 16 avhandlingar innehållade ordet Kärnenergiteknik.

  1. 1. Development of Encapsulated UN-UO₂ Accident Tolerant Fuel

    Författare :Diogo Ribeiro Costa; Pär Olsson; Janne Wallenius; Simon Middleburgh; Magnus Limbäck; Denise Adorno Lopes; Ho Jin Ryu; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Accident tolerant fuel; UN-UO2 composite fuel; coating technology; powder coating; chemical vapour deposition CVD ; physical vapour deposition PVD ; UN spheres; spark plasma sintering; Kärnenergiteknik; Nuclear Engineering;

    Sammanfattning : Accident tolerant fuels (ATFs) are designed to endure a severe accident in the reactor core longer than the standard UO2-Zr alloy systems used in light water reactors (LWRs). Composite fuels such as UN-UO2 are being considered as an ATF concept to address the lower oxidation resistance of the UN fuel from a safety perspective for use in LWRs, whilst improving the in-reactor behaviour of the UO2 fuel. LÄS MER

  2. 2. Mechanistic Modeling of Annular Flows at Near-Dryout Conditions

    Författare :Wenyuan Fan; Henryk Anglart; Martin Rohde; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Kärnenergiteknik; Nuclear Engineering;

    Sammanfattning : This work aims at advancing the modeling methodology for near-dryout annular flows using two different computational fluid dynamics (CFD) approaches. One is termed as the transported film approach, where the film flow is separately modeled by a simplified liquid film model and then coupled with the gas core simulation using various closures. LÄS MER

  3. 3. Response Matrix Reloaded : for Monte Carlo Simulations in Reactor Physics

    Författare :Mickus Ignas; Jan Dufek; Jaakko Leppänen; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Kärnenergiteknik; Nuclear Engineering;

    Sammanfattning : This thesis investigates Monte Carlo methods applied to criticality and time-dependent problems in reactor physics. Due to their accuracy and flexibility, Monte Carlo methods are considered as a “gold standard” in reactor physics calculations. However, the benefits come at a significant computing cost. LÄS MER

  4. 4. Ab initio driven modeling of advanced nuclear fuels

    Författare :Huan Liu; Pär Olsson; Marjorie Bertolus; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Fysik; Physics; Kärnenergiteknik; Nuclear Engineering;

    Sammanfattning : With the development of clean energy sources such as nuclear power, it has become more important to use advanced nuclear fuels to improve economic efficiency and expand safety margins. Thanks to the high fissile density, high thermal conductivity, and high melting point, uranium nitride and uranium silicide have been considered accident tolerant or high-performance fuels for commercial light water reactors and for future generation reactor systems. LÄS MER

  5. 5. Towards Efficient Monte Carlo Calculations in Reactor Physics : Criticality, Kinetics and Burnup Problems

    Författare :Ignas Mickus; Jan Dufek; Andrea Zoia; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Kärnenergiteknik; Nuclear Engineering;

    Sammanfattning : This thesis presents a compilation of work focused on Monte Carlo crit-icality, kinetics and burnup calculations in reactor physics. Performing suchcalculations usually comes at a high computing cost. Therefore, the main mo-tivation behind the presented work is lowering the computing cost of MonteCarlo calculations. LÄS MER