Sökning: "thermal stresses"

Visar resultat 1 - 5 av 86 uppsatser innehållade orden thermal stresses.

  1. 1. High Temperature Tribology of Exhaust Components in Alternative Fuel Engines

    Master-uppsats, Luleå tekniska universitet/Institutionen för teknikvetenskap och matematik

    Författare :Muhammad Hashir Zaheer; [2023]
    Nyckelord :High temperature tribology; Wear; Friction; Exhaust manifold; Lip seal ring; Wear resistant coatings; Inconel 718c; SiMo51 ductile cast iron; AlTiN; Tribaloy 400;

    Sammanfattning : Internal Combustion Engine (ICE) exhaust components are exposed to extreme operating temperatures. Thus, it is necessary that they are designed with materials that can sustain thermal and vibrational stresses. LÄS MER

  3. 2. Impact of Residual Stress on the Warm Pre-Stressing Effect

    Master-uppsats, KTH/Hållfasthetslära

    Författare :Emil Danielsson; [2023]
    Nyckelord :Warm Pre-Stressing effect; Residual stress; Cleavage fracture; Ferritic Steel; Fracture mechanics; Varm förspänning; Restspänningar; Klyvbrott; Brottmekanik; Ferritiskt stål;

    Sammanfattning : Irradiation of a reactor pressure vessel (RPV) causes a shift of the ductile to brittle transition region towards higher temperature regions. In the event of a pressurized thermal shock (PTS), where the temperature drops drastically, the ductile to brittle transition region might be entered for irradiated ferritic steel. LÄS MER

  4. 3. Visualization, modeling and consequences of residual stresses in glass frit sealing of a UV light source

    Uppsats för yrkesexamina på avancerad nivå, Uppsala universitet/Mikrosystemteknik

    Författare :Vilma Hurtigh Grabe; [2023]
    Nyckelord :bonding; micro system; glass frit; sealing; finite element; modeling; glass; mikrosystem; sammanfogning; glasfog; fog; finita element; modellering; glas;

    Sammanfattning : PureFize Technologies AB develops and manufactures a broadband ultraviolet (UVC) light technology device that is mercury-free and based on nanotechnology, using the principle of field emission. The light source is made of Ti and glass, which are hermetically bonded, using a low-temperature glass frit, at elevated temperatures. LÄS MER

  5. 4. 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

  7. 5. Investigation of MIDEL 7131’s Dielectric Breakdown Strength and Thermal Behaviour : Master Thesis, an experimental study using concentric-like electrodes at elevated temperatures to study breakdowns

    Master-uppsats, KTH/Skolan för elektroteknik och datavetenskap (EECS)

    Författare :Kim Lin; [2023]
    Nyckelord :Dielectric strength; High voltage; Liquid dielectric; MIDEL 7131; Electrical breakdown; Temperature cycle; Dielektrisk styrka; Högspänning; Dielektriska vätskor; MIDEL 7131; Elektrisk nedbrytning; Temperaturcykling;

    Sammanfattning : Dielectric insulation are constantly exposed to various stresses, while also being expected to last for long periods of time. Naturally, they degrade with use and in demanding operational environments, this degradation phenomena can be accelerated, leading to costly consequences. LÄS MER