Sökning: "stratified flows"

Visar resultat 1 - 5 av 7 uppsatser innehållade orden stratified flows.

  1. 1. Computational Fluid Dynamics and Modeling of a Free Surface Flow

    Master-uppsats, KTH/Skolan för teknikvetenskap (SCI)

    Författare :Mathieu Marmier; [2023]
    Nyckelord :CFD; Free Surface Flow; VOF; STAR-CCM ; Multiphase Simulation; Nuclear Engineering; Fluid Mechanics;

    Sammanfattning : This project deals with the CFD modelling of a free surface flow. The aim is to develop and validate a fast and accurate numerical model for stratified two-phase flows. Volume of Fluid (VOF) multiphase model is employed. The purpose is to use the developed numerical model for the design of an element within a compact nuclear reactor. LÄS MER

  3. 2. Verification and validation of the implementation of an Algebraic Reynolds-Stress Model for stratified boundary layers

    Master-uppsats, KTH/Teknisk mekanik

    Författare :Martina Formichetti; [2022]
    Nyckelord :Atmospheric boundary layer; turbulence modelling; stratified flows; eddy viscosity; eddy diffusivity;

    Sammanfattning : This thesis studies the implementation of an Explicit Algebraic Reynolds-Stress Model(EARSM) for Atmospheric Boundary Layer (ABL) in an open source ComputationalFluid Dynamics (CFD) software, OpenFOAM, following the guidance provided by thewind company ENERCON that aims to make use of this novel model to improvesites’ wind-field predictions. After carefully implementing the model in OpenFOAM,the EARSM implementation is verified and validated by testing it with a stratifiedCouette flow case. LÄS MER

  4. 3. Simulation of IB-LOCA in TRACE : A semi-blind study of numerical simulations compared to the PKL test facility

    Uppsats för yrkesexamina på avancerad nivå, Uppsala universitet/Tillämpad kärnfysik

    Författare :Matilda Tiberg; [2022]
    Nyckelord :Pressurized Water Reactor; Safetey analysis; LOCA; Intermediate Break; PKL; TRACE; transient; thermal hydraulics;

    Sammanfattning : This thesis studied the performance of the thermal hydraulic software TRACE applied on an intermediate sized break (IB) happening on the cold leg in a pressurized water reactor (PWR), causing a loss-of-coolant accident (LOCA). The same accident has previously been simulated in the PKL Test Facility, which is a scaled version of a PWR and is used to simulate transients stemming from different accidents. LÄS MER

  5. 4. Modellering av fosfordynamik i Stora och Lilla Ullfjärden

    Uppsats för yrkesexamina på avancerad nivå, Uppsala universitet/Luft-, vatten- och landskapslära

    Författare :Walter Cassel; [2022]
    Nyckelord :HYPE; fosfordynamik; internbelastning; fosforbelastning; Stora Ullfjärden; Lilla Ullfjärden; algblomning;

    Sammanfattning : Algblomningar är ett problem i många svenska sjöar, speciellt när cyanobakterier blommar och producerar cyanotoxiner. En förutsättning för algblomningar är en tillräckligt hög fosforhalt, då fosfor ofta är det begränsande näringsämnet för cyanobakterier. LÄS MER

  7. 5. The Inclusion of Stratification in Wind Analysis; A New Linearized Code

    Master-uppsats, KTH/Strömningsmekanik och Teknisk Akustik

    Författare :Roland Nyberg; [2020]
    Nyckelord :Wind Energy; Stratification; Speed-up effect; Monin-Obukhov similarity theory; Vindenergy; Stratifikation; Speed-up effekt; Monin-Obukhov teori;

    Sammanfattning : Wind energy is rapidly growing around the world as non-renewable energy sources are being phased out. To maximize the energy production, it is crucial to construct new wind turbines at locations where the average wind speed is high. An accurate wind assessment of a new potential site is thus essential in the development of new wind farms. LÄS MER