Sökning: "bränsleceller"

Visar resultat 6 - 10 av 33 avhandlingar innehållade ordet bränsleceller.

  1. 6. Solid Oxide Fuel Cell Modeling at the Cell Scale - Focusing on Species, Heat, Charge and Momentum Transport as well as the Reaction Kinetics and Effects

    Författare :Martin Andersson; Värmeöverföring; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; SOFC; anode-supported; modeling; CFD; charge species heat momentum transport; electrochemical internal reforming reactions; TPB; area-to-volume ratio; COMSOL Multiphysics;

    Sammanfattning : Fuel cells are electrochemical devices that directly transform chemical energy into electricity. They are promising for future energy systems, since they are energy efficient, able to use renewable fuels and, when hydrogen is used as fuel, there are no direct emissions of greenhouse gases. LÄS MER

  3. 7. Structure and dynamics of complex materials in the water-poor regime

    Författare :Sanna Gustavsson; Fysikalisk kemi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Hydration; cellulose; dissolution; sugar surfactant; hydrated crystals; structure; dynamics; phase diagram; fuel cell; pulsed-field-gradient PFG spin-echo NMR; Polarization Transfer solid state NMR; PXRD; GVS; TGA; amphiphilic;

    Sammanfattning : In the solid state, molecules are normally ordered in a specific structure. With time, and as a result of influence from the surroundings, solid materials can change their molecular and/or crystal structure and, as a consequence, obtain completely different properties. Water is particularly important in this respect. LÄS MER

  4. 8. Synthesis and characterization of palladium based carbon nanostructure-composites and their clean-energy application

    Författare :Florian Nitze; Thomas Wågberg; Ludvig Edman; Kordas Krisztian; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Carbon nanostructures; chemical vapour deposition; electro catalysts; transmission electron microscopy; direct formic acid fuel cells; Solid State Physics; fasta tillståndets fysik;

    Sammanfattning : Carbon nanostructures are a wide field with many applications. The use of carbon nanostructures as support in heterogeneous catalysis is a key development that led together with the use of nanoparticles to a significant cost reduction of catalysts. Catalysts designed in this way are widely applied in fuel cell technologies. LÄS MER

  5. 9. Multiphysics modelling of PEM fuel cells - with reacting transport phenomena at micro and macroscales

    Författare :Munir Khan; Värmeöverföring; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; macroscale; PEM fuel cells; CFD; microscale; multiphysics; multiphase; anisotropy;

    Sammanfattning : This thesis presents numerical simulations of reacting transport phenomena in polymer electrolyte membrane (PEM) fuel cells. Broadly, the presented work is subdivided into macro and microscale simulations. LÄS MER

  7. 10. Limiting processes in anion-exchange membrane fuel cells

    Författare :Henrik Grimler; Göran Lindbergh; Rakel Wreland Lindström; Carina Lagergren; Marc Secanell; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; anion-exchange membrane fuel cell; hydrogen oxidation reaction; oxygen reduction reaction; water transport; physics-based modelling; Chemical Engineering; Kemiteknik;

    Sammanfattning : Fuel cells allow for converting chemical energy stored in hydrogen into electrical energy, with only heat and water as by-products. In a sustainable energy society, hydrogen may play an important role due to its ability to act both as an energy carrier and as a valuable chemical in the process industry. LÄS MER