Sökning: "numerical performance"

Visar resultat 11 - 15 av 821 avhandlingar innehållade orden numerical performance.

  1. 11. Ghosts and machines : regularized variational methods for interactive simulations of multibodies with dry frictional contacts

    Författare :Claude Lacoursière; Bo Kåggström; Ander Klarbring; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Discrete mechanics; Variational method; Contact problems; Impacts; Least action principle; Saddle point problems; Lagrange Multipliers; Constrained systems; Multibody Systems; Numerical regularization; Constraint realization; Constraint stabilization; Dry friction; Differential Algebraic Equations; Nonsmooth problems; Linear Complementarity; Quaternion algebra; Numerical linear algebra; Physics modeling; Interactive simulation; Numerical stability; Rigid body dynamics; Dissipative systems; Computational physics; Beräkningsfysik;

    Sammanfattning : A time-discrete formulation of the variational principle of mechanics is used to provide a consistent theoretical framework for the construction and analysis of low order integration methods. These are applied to mechanical systems subject to mixed constraints and dry frictional contacts and impacts---machines. LÄS MER

  3. 12. Analysis of Deformation of Gas Diffusion Layers and the Impact on Performance of PEM Fuel Cells

    Författare :Jiatang Wang; Värmeöverföring; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; PEM fuel cell; compression ratio; assembly pressure; porosity; deformed GDL; electric resistance; transport phenomena; model; performance; analysis; OpenFOAM;

    Sammanfattning : Proton exchange membrane (PEM) fuel cells have been promoted due to significant breakthroughs in various aspects and increasing public interests. The porous features of the gas diffusion layer (GDL) and the necessary assembly processes generate localized pressure forces on the channel/shoulder structure of the bi-polar plates (BPP). LÄS MER

  4. 13. Mathematical modeling and numerical tools for simulation and design of light scattering in paper and print

    Författare :Per Edström; Mittuniversitetet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; mathematical modeling; radiative transfer; integro-differential equations; inverse problems; parameter estimation; solution method; numerical performance; light scattering; paper industry applications; Kubelka-Munk; MATHEMATICS; MATEMATIK;

    Sammanfattning : This work starts with a real industrial problem - the perceived need for a moredetailed and more accurate model for light scattering in paper and print than theKubelka‐Munk model of today. A careful analysis transfers this problem into aphysical description of the phenomena involved. LÄS MER

  5. 14. FRCM-Composites for Strengthening Concrete Walls with Openings : Experimental and Numerical Analysis

    Författare :Cristian Sabau; Björn Täljsten; Thomas Blanksvärd; Gabriel Sas; Cosmin Popescu; Thanasis C. Triantafillou; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; FRCM; reinforced concrete; walls; openings; strenghtening; Structural Engineering; Konstruktionsteknik;

    Sammanfattning : Upgrading existing buildings to new functional requirements may require new openings that can weaken the structure, prompting the need for strengthening. In such cases, traditional strengthening solutions, such as creating a reinforced concrete or steel frame around the opening, imply long-term restrictions in the use of the structure. LÄS MER

  7. 15. Predictions of manufacturing induced shape distortions : high performance thermoset composites

    Författare :J. Magnus Svanberg; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Polymera konstruktionsmaterial; Polymeric Composite Materials;

    Sammanfattning : High performance composites usually consist of continuous fibres and a thermoset matrix. A well-known example is carbon fibre epoxy composites. When this kind of material is cured residual stresses and/or shape distortions are produced owing to thermally and chemically induced volumetric strains. LÄS MER