Search for dissertations about: "melt pool"

Showing result 1 - 5 of 55 swedish dissertations containing the words melt pool.

  2. 1. Conduction laser welding : modelling of melt pool with free surface deformation

    Author : Josefine Svenungsson; Högskolan Väst; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Conduction laser welding; numerical modelling; Computational Fluid Dynamics; OpenFOAM; free surface deformation; melt pool; Production Technology; Produktionsteknik; Manufacturing and materials engineering; Produktions- och materialteknik;

    Abstract : Laser welding is commonly used in the automotive-, steel- and aerospace industry. It is a highly non-linear and coupled process where the weld geometry is strongly affected by the flow pattern in the melt pool. Experimental observations are challenging since the melt pool and melt flow below the surface are not yet accessible during welding. READ MORE

  4. 2. Melt flow and surface stability effects on polymer flammability : A study on polystyrene, flexible polyurethane foam and polyolefin composites

    Author : Roland H. Krämer; Ulf W. Gedde; Norman C. Billingham; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Melt; flow; dripping; collapse; combustion; pool fire; feed‐back; gasification; heat release; flammability; nanocomposites; molar mass; intumescence; polyurethane; Polymer chemistry; Polymerkemi;

    Abstract : Our ability to accurately determine the flammability properties of polymers is hampered bythe erratic effects of deformation and liquid flow that occur during polymer combustion.This study aims to improve the understanding of such effects at several levels: The often obvious impact of melt flow on standardized flammability test methods forelectrical appliances is described to identify the need and to motivate others to worktowards an improved material characterization. READ MORE

  5. 3. Metal fusion using pulsed GasMetal Arc : Melt pool modellingand CFD simulation

    Author : Pradip Aryal; Isabelle Choquet; Muriel Carin; Högskolan Väst; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Gas metal arc; Electromagnetic force modelling; Free surface deformation; Computational Fluid Dynamics; OpenFOAM; Gasmetallbågsvetsning; Svetsläge; Elektromagnetiskkraftmodellering; Smältytans rörelser; Computational Fluid Dynamics; OpenFOAM; Production Technology; Produktionsteknik;

    Abstract : Pulsed gas metal arc is a highly efficient technique used in manufacturing processes like welding and additive manufacturing. It offers high productivity and cost benefits but it is also prone to defect formation when process parameters are not properly controlled and optimized. READ MORE

  6. 4. Gas Metal Arc Melt Pool Modelling : Effect of welding position and electromagnetic force mode

    Author : Pradip Aryal; Isabelle Choquet; Högskolan Väst; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Gas metal arc welding; Gravitational force; Substrate orientation; Electromagnetic force modelling; Free surface deformation; Computational Fluid Dynamics; OpenFOAM; Gasmetallbågsvetsning; Gravitation; Svetsläge; Elektromagnetisk kraftmodellering; Smältytans rörelser; Computational Fluid Dynamics; OpenFOAM; Production Technology; Produktionsteknik;

    Abstract : Gas metal arc is a high-efficiency and widely used heat source for metal processing applied predominantly in welding and additive manufacturing. In this study, it was applied to welding. READ MORE

  7. 5. The Effective Convectivity Model for Simulation and Analysis of Melt Pool Heat Transfer in a Light Water Reactor Pressure Vessel Lower Head

    Author : Chi Thanh Tran; Tomas Lefvert; Harri Tuomisto; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; light water reactor; hypothetical severe accident; accident progression; accident scenario; core melt pool; heat transfer; turbulent natural convection; heat transfer coefficient; phase change; mushy zone; crust; lower plenum; analytical model; effective convectivity model; CFD simulation; Thermal energy engineering; Termisk energiteknik;

    Abstract : Severe accidents in a Light Water Reactor (LWR) have been a subject of intense research for the last three decades. The research in this area aims to reach understanding of the inherent physical phenomena and reduce the uncertainties in their quantification, with the ultimate goal of developing models that can be applied to safety analysis of nuclear reactors, and to evaluation of the proposed accident management schemes for mitigating the consequences of severe accidents. READ MORE