Search for dissertations about: "large machines"

Showing result 1 - 5 of 219 swedish dissertations containing the words large machines.

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

    Author : Claude Lacoursière; Bo Kåggström; Ander Klarbring; Umeå universitet; []
    Keywords : 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;

    Abstract : 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. READ MORE

  4. 2. Heat-transfer simulations applied to electrical machines

    Author : Kristian Rönnberg; Christophe Duwig; Jens Walther; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; energy efficiency; heat transfer; electric machines; high fidelity simulation; modal analysis; Engineering Mechanics; Teknisk mekanik; Electrical Engineering; Elektro- och systemteknik;

    Abstract : Electrification and energy efficiency are two important aspects in present scenarios describing a sustainable future. Electric motors constitute a large fractionof industry’s electricity demand today, and it is expected to remain high inthe future. READ MORE

  5. 3. Numerical predictions of heat-transfer applied to electrical machines

    Author : Kristian Rönnberg; Christophe Duwig; Anders Dahlkild; Luca Peretti; Jens Honore Walther; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electric machines; energy efficiency; heat transfer; thermal management; high fidelity simulation; computational fluid dynamics CFD ; proper orthogonal decomposition POD ; lumped parameter thermal network LPTN ; Elektriska maskiner; energieffektivitet; verkningsgrad; värmeöverföring; värmehantering; simuleringar med hög upplösning; strömningsmekaniska beräkningar; proper orthogonal decomposition POD ; termiska nätverk; Teknisk mekanik; Engineering Mechanics;

    Abstract : In order to meet the need for increased electrification, and at the same time reduce the total demand for electric energy, behavior change and technological innovation is needed. Over the decades power density of electric motors have increased, leading to increased demands on the cooling system design and performance. READ MORE

  6. 4. Robotized Production Methods for Special Electric Machines

    Author : Erik Hultman; Mats Leijon; Jörg Franke; Uppsala universitet; []
    Keywords : Industrial robotics; Assembly automation; Large-scale production; Cable winding; Linear generator; Wave energy converter; Wave power; Engineering education; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

    Abstract : A research project on renewable energy conversion from ocean waves to electricity was started at the Division of Electricity at Uppsala University (UU) in 2001. The Wave Energy Converter (WEC) unit developed in this project is intended to be used in large offshore WEC farms and has therefore been designed with large-scale production in mind. READ MORE

  7. 5. A New Paradigm for Large Brushless Hydrogenerators : Advantages Beyond the Static System

    Author : Jonas Kristiansen Nøland; Urban Lundin; Phil Mellor; Uppsala universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Brushless exciters; Rotating exciters; Permanent Magnet Machines; Synchronous Generator Excitation; Thyristor Rectifiers; Chopper Rectifiers; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

    Abstract : The grid code, FIKS, from the Norwegian transmission system operator (TSO), Statnett, states that synchronous generators > 25MVA, must have a static excitation system. However, an improved brushless excitation system is in operation on some commercial power plants (36MVA, 93.75rpm & 52MVA, 166. READ MORE