Sökning: "free surface"

Visar resultat 1 - 5 av 939 avhandlingar innehållade orden free surface.

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

    Författare :Josefine Svenungsson; Högskolan Väst; []
    Nyckelord :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;

    Sammanfattning : 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. LÄS MER

  2. 2. Potential Flow Panel Methods for the Calculation of Free-surface Flows with Lift

    Författare :Carl-Erik Janson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; desingularized; shape optimization; Rankine source; waves; OCTOPUS; dipole; MMA; Dawson operator; boundary layer; vortex; Method of Moving Asymptotes; nonlinear; sailing yacht; four point operator; surface piercing wing; Navier-Stokes; numerical method; lift force; raised panel method; discrete Fourier transform; collocation point shift; potential flow; CFD; free surface; induced drag; SHIPFLOW; dispersion; damping; analytical method; hydrofoil;

    Sammanfattning : Two non-linear Rankine-source panel methods are developed and implemented in the same computer code. The first method uses a four-point upwind operator on the free-surface to compute the velocity derivatives and to enforce the radiation condition while the second method uses an analytical expression for the velocity derivatives and a collocation point shift one panel upstream to prevent upstream waves. LÄS MER

  3. 3. From Macro to Nano : Electrokinetic Transport and Surface Control

    Författare :Gaspard Pardon; Wouter van der Wijngaart; Philippe Renaud; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; microsystem; nanosystem; microfluidic; nanofluidic; surface modification; surface property; electrokinetics; model; simulation; material; polymer; thiol-ene; microfabrication; nanofabrication; micromanufacturing; nanomanufacturing; breath sampling; aerosol precipitation; corona discharge; electrostatic precipitation; grafting chemistry; click chemistry; nanopore; nanoporous membrane; photolithography; photopatterning; photografting; microfluidics; nanofluidics; oste; OSTE ; OSTEmer; lab-on-chip; loc; point-of-care; poc; biocompatibility; diagnostics; breath analysis; fuel cell; Electrical Engineering; Elektro- och systemteknik; Teknisk materialvetenskap; Materials Science and Engineering; Fysik; Physics; Medical Technology; Medicinsk teknologi;

    Sammanfattning : Today, the growing and aging population, and the rise of new global threats on human health puts an increasing demand on the healthcare system and calls for preventive actions. To make existing medical treatments more efficient and widely accessible and to prevent the emergence of new threats such as drug-resistant bacteria, improved diagnostic technologies are needed. LÄS MER

  4. 4. Covalent Surface Modification of Degradable Polymers for Increased Biocompatibility

    Författare :Martina Källrot; Ann-Christine Albertsson; Mikael Lindström; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Vapor phase grafting; covalent surface modification; solvent free; nano patterned topography; degradable polymers; poly ε-caprolactone ; poly L-lactide ; poly lactide-co-glycolide ; poly trimethylene carbonate ; N-vinylpyrrolidone; maleic anhydride; acrylamide; Gasfasympning; kovalent ytmodifiering; lösningsmedelsfri; nedbrytbara polymerer; nanomönstrad topografi; poly L-laktid ; poly ε-kaprolakton ; poly laktid-co-glykolid ; poly trimetylen karbonat ; N-vinylpyrrolidon; maleinsyraanhydrid; akrylamid; Polymer chemistry; Polymerkemi;

    Sammanfattning : Degradable polymers have gained an increased attention in the field of biomedical applications over the past decades, for example in tissue engineering. One way of improving the biocompatibility of these polymers is by chemical surface modification, however the risk of degradation during the modification procedure is a limiting factor. LÄS MER

  5. 5. Stability of the free-surface problem arising in ice-sheet- and glacier modeling : Numerical investigation and stabilization

    Författare :André Löfgren; Josefin Ahlkrona; Fabien Gillet-Chaulet; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Ice-sheet modeling; glacier modeling; ice-sheet dynamics; free-surface flow; stability; stabilization; free-surface stabilization algorithm; Numerical Analysis; numerisk analys;

    Sammanfattning : This thesis consists of two papers dealing with a stabilization method for free-surface flows. The method was initially developed to stabilize mantle-convection simulations, but is in this work extended to ice-sheet- and glacier modeling. LÄS MER