Sökning: "cfd nuclear"

Visar resultat 1 - 5 av 16 avhandlingar innehållade orden cfd nuclear.

  1. 1. Validation and Application of CFD to Safety-Related Phenomena in Lead-Cooled Fast Reactors

    Författare :Marti Jeltsov; Pavel Kudinov; Walter Villanueva; Dmitry Grishchenko; Afaque Shams; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Verification; Validation; Calibration; Sensitivity Analysis; Uncertainty Analysis; CFD; STH; Code Coupling; Liquid Lead Coolant; LFR; SGTL R; Bubble transport; Core voiding; Seismic Sloshing; Melting Solidification; Physics; Fysik;

    Sammanfattning : Carbon-free nuclear power production can help to relieve the increasing energy demand in the world. New generation reactors with improved safety, sustainability, reliability, economy and security are being developed. Lead-cooled fast reactor (LFR) is one of them. LÄS MER

  3. 2. Development of fine-mesh methodologies for coupled calculations in Light Water Reactors

    Författare :Klas Jareteg; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; CFD; Coupled neutronics thermal-hydraulics; nuclear reactor multiphysics; multiphase flow;

    Sammanfattning : This thesis presents fine-mesh multiphysics methodologies and algorithms for numerical predictions of the behavior of Light Water Reactor (LWR) cores. The multiphysics aspects cover the distribution of neutrons, the fluid flow of the coolant and the conjugate heat transfer between the solid fuel pins and the fluid coolant. LÄS MER

  4. 3. Pulsed Neutron Activation for Determination of Water Flow in Pipes

    Författare :Håkan Mattsson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Flowmeter; Pulsed Neutron Activation; CFD; Pipe flow; PNA;

    Sammanfattning : In a Pulsed Neutron Activation (PNA) flowmeter neutron induced activity is used to measure water flow in pipes. The water in the pipe is bombarded with neutron pulses which introduce activity into the pipe. The activity is then transported and mixed with the flow. LÄS MER

  5. 4. Volumetric MRI measurements of velocity and flow - Accuracy, visualisation and technical improvements

    Författare :Anders Nilsson; Lund Medicinsk strålningsfysik; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MRI; 4D flow; phase contrast MRI; velocity mapping;

    Sammanfattning : In the last two decades, phase-contrast magnetic resonance imaging (PC-MRI) has evolved from two-dimensional velocity and flow measurements to volumetric, time-resolved depictions of velocity fields (4D PC). The acquisition of time-resolved velocity fields allows flow visualisations that might provide better understanding of the dynamics of the cardiac system. LÄS MER

  7. 5. 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