Sökning: "damper"

Visar resultat 21 - 25 av 52 avhandlingar innehållade ordet damper.

  1. 21. Modelling and analysis of multiphysical interactions in hydropower rotor systems

    Författare :Martin Karlsson; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Datorstödd maskinkonstruktion; Computer Aided Design;

    Sammanfattning : In this thesis the objective is to develop rotordynamical models of hydropower units, where coupling between mechanical, electromagnetic and fluid dynamical system systems is of certain interest. Both fluid-rotor and electromechanical interactions are known to change the system coefficients of the rotor system, which affects eigenfrequencies, damping, stability and response. LÄS MER

  3. 22. Vibration mitigation of high-speed railway bridges : Application of damping devices in theory and practice

    Författare :Sarah Tell; Raid Karoumi; Andreas Andersson; Ülker-Kaustell Mahir; José Maria Goicolea; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vibration mitigation; high-speed railway bridges; damping devices; retrofit; numerical analysis; hybrid simulation; field experiment; vibrationsdämpning; järnvägsbroar för höghastighetståg; dämpare; eftermonteringsmetod; numerisk analys; hybridsimulering; fältförsök; Structural Engineering and Bridges; Bro- och stålbyggnad;

    Sammanfattning : The dynamic response of railway bridges is an important aspect to consider, as the repetitive loading from passing trains may result in excessive vibrations of the bridge deck. Several design criteria are developed in order to assure the structural safety and passenger comfort during train crossings of a bridge. LÄS MER

  4. 23. On Stabilization of Sensorless Synchronous Motor Drives and Traction Converters

    Författare :Magnus Jansson; Lennart Harnefors; Mats Alakula; Mälardalens högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electronics; Elektronik; elektronik; Electronics;

    Sammanfattning : Avhandlingen behandlar först och främst styrning av elmotordrifter, men vi tittar även på styrning av nätomriktare för stabil framdrivning av tåg.Två industriprojekt är rapporterade i avhandlingen, i form av delrapporterna ”Sensorless Control of Electrically Excited Synchronous Machines”, ABB Corporate Research och ”Stable and Passive Traction”, Bombardier Transportation. LÄS MER

  5. 24. Modelling and Experimental Verification of Direct Drive Wave Energy Conversion : Buoy-Generator Dynamics

    Författare :Mikael Eriksson; Mats Leijon; Jan Isberg; Arne Wolfbrandt; Kim Nielsen; Uppsala universitet; []
    Nyckelord :Engineering physics; Wave energy; Potential wave theory; Linear generator; Simulations; Experiments; Point absorber; FEM; Equivalent circuit theory; Teknisk fysik; TECHNOLOGY; TEKNIKVETENSKAP;

    Sammanfattning : This thesis is focused on development of models and modelling of a wave energy converter in operation. Through the thesis linear potential wave theory has been used to describe the wave-buoy interaction. The differences lie in the generator models, in the simplest model the generator is a mechanical damper characterized by a damping factor. LÄS MER

  7. 25. Simulation methods for bumper system development

    Författare :Erik Isaksson; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hållfasthetslära; Solid Mechanics;

    Sammanfattning : n development of bumper systems for the automotive industry, iterative Finite Element (FE) simulations are normally used to find a bumper design that meets the requirements of crash performance. The crash performance of a bumper system is normally verified by results from standardized low speed crash tests based on common crash situations. LÄS MER