Sökning: "Low boundary conditions"

Visar resultat 1 - 5 av 78 uppsatser innehållade orden Low boundary conditions.

  1. 1. Insights Into Wind Profile Characteristics in the Arctic Marine Boundary Layer

    Master-uppsats, Uppsala universitet/Luft-, vatten- och landskapslära

    Författare :Charlotte Sophie Gausa; [2024]
    Nyckelord :Arctic; wind profile power law; MOST; boundary layer; low level jets; sea ice; vindprofil; Arktis; gränsskikt; vindenergi; låghöjdsvindar; havsis;

    Sammanfattning : The atmospheric boundary layer in the Arctic is essential for the understanding of climate change and improving regional weather prediction. The aim of this study is to investigate to which degree wind speed profiles retrieved in the Arctic agree with well known wind profile concepts and understand which local impact factors influence the wind speed profile. LÄS MER

  3. 2. Solving the incompressible Navier-Stokes equations in 3-D to model gas flow in a room

    Uppsats för yrkesexamina på avancerad nivå, Uppsala universitet/Avdelningen för beräkningsvetenskap

    Författare :Fredrik Malmström; [2024]
    Nyckelord :;

    Sammanfattning : The thesis proposes to model the flow of gases in a room by solving the incompressible Navier-Stokes equations in three dimensions. The transportationof scalars such as temperature and concentration of CO2 is modeled by solving the advection-diffusion equation, and the effects of temperature on thevelocity is accounted for by employing the Boussinesq approximation. LÄS MER

  4. 3. Investigation of coarse-grid CFD approach for nuclear engineering application

    Master-uppsats, KTH/Fysik

    Författare :Michela Casarella; [2023]
    Nyckelord :Thermal-hydraulics; Nuclear reactor; CFD; Sub-channel; Coarse-grid; Turbulence; Pressure drop; Termisk-hydraulik; kärnreaktor; CFD; underkanal; grovkornigt nät; turbulens; tryckfall;

    Sammanfattning : In this thesis, an innovative coarse grid CFD approach is developed that aims toexploit the capabilities of sub-channel codes and CFD methods while overcoming theirlimitations. In the approach, a very coarse mesh is implemented in the CFD softwareOpenFOAM and a new wall treatment, based on the traditional concept of the wallfunction, is applied to the wall boundary conditions of the domain to take into accountthe low resolution of the grid which does not allow to effectively capture the effect of thesolid walls on the thermo-hydraulics of the flow. LÄS MER

  5. 4. An analytical method for quickly evaluating the performances of refractory alloys in sCO2 Brayton cycle applications

    Master-uppsats, KTH/Skolan för industriell teknik och management (ITM)

    Författare :Jiaqi Yang; [2023]
    Nyckelord :;

    Sammanfattning : A rapid and effective analytical method has been developed to assess the performance of structural materials in sCO2 power cycle applications. This method combines a conjugate heat transfer model, considering constant heat flux boundary conditions, with a corresponding mechanical model. LÄS MER

  7. 5. Simulation of low frequency acoustic waves in small rooms : An SBP-SAT approach to solving the time dependent acoustic wave equation in three dimensions

    Kandidat-uppsats,

    Författare :Alva Fährlin; Olle Edgren Schüllerqvist; [2023]
    Nyckelord :room acoustics; numerical methods; SBP; SAT; acoustic wave equation.;

    Sammanfattning : Low frequency acoustic room behaviour can be approximated using numerical methods. Traditionally, music studio control rooms are built with complex geometries, making their eigenmodes difficult to predict mathematically. LÄS MER