Sökning: "vibrationer vakuumteknik akustik hydraulik Maskinteknik vacuum technology vibration and acoustic eng"

Visar resultat 21 - 25 av 45 avhandlingar innehållade orden vibrationer vakuumteknik akustik hydraulik Maskinteknik vacuum technology vibration and acoustic eng.

  1. 21. Variable Valve Actuation in a Spark Ignition Engine - A Flow Field and Heat Release Study

    Författare :Fredrik Söderberg; Förbränningsmotorer; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; framdrivningssystem; Gases; plasma; fluid dynamics; plasmas; Gaser; fluiddynamik; vakuumteknik; vibrationer; akustik; Motors and propulsion systems; Motorer; hydraulik; Maskinteknik; vibration and acoustic engineering; Laser Doppler Velocimetry Particle Image Velocimetry PIV LDV Wavelet Computational Fluid Dynamics CFD Variable Valve Actuation Timing Turbulence Combustion Engine Spark Ignition Miller; hydraulics; vacuum technology; Mechanical engineering;

    Sammanfattning : The objective of this thesis was to find ways of improving part-load efficiency for a spark ignition engine by studying the effects of variable-valve actuation on fluid flow and combustion. The in-cylinder flow was measured with laser doppler velocimetry, LDV, and particle image velocimetry, PIV. LÄS MER

  2. 22. Applications of the Complex Modulation Transfer Function on SEA-systems

    Författare :Karl-Ola Lundberg; Teknisk akustik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vacuum technology; hydraulics; Mechanical engineering; modulated noise; in-situ; modulation transfer function; loss factor; SEA; vibration and acoustic engineering; Maskinteknik; hydraulik; vakuumteknik; vibrationer; akustik;

    Sammanfattning : The SEA coupling and dissipation loss factors are determined in-situ from Complex Modulation Transfer Functions, CMTF:s, based on measured impulse-responses. A quotient of CMTF:s is least-square curve-fitted to a SEA model and the SEA loss factors are determined from the results of the curve-fit. LÄS MER

  3. 23. Estimation of the In-Cylinder Air/Fuel Ratio of an Internal Combustion Engine by the Use of Pressure Sensors

    Författare :Per Tunestål; Förbränningsmotorer; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vakuumteknik; hydraulik; Maskinteknik; nonlinear; cylinder pressure; engine; least-squares; Mechanical engineering; estimation; hydraulics; vibration and acoustic engineering; vacuum technology; vibrationer; akustik; Motors and propulsion systems; Motorer; framdrivningssystem;

    Sammanfattning : This thesis investigates the use of cylinder pressure measurements for estimation of the in-cylinder air/fuel ratio in a spark ignited internal combustion engine. An estimation model which uses the net heat release profile for estimating the cylinder air/fuel ratio of a spark ignition engine is developed. LÄS MER

  4. 24. Branch Identification in Elastic Stability Analysis

    Författare :Anders Magnusson; Hållfasthetslära; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vacuum technology; hydraulics; Mechanical engineering; Produktionsteknik; Production technology; FEM; computer simulation; bifurcation; stability; vibration and acoustic engineering; Maskinteknik; hydraulik; vakuumteknik; vibrationer; akustik;

    Sammanfattning : In this thesis, methods to determine the static postbuckling behaviour of elastic structures undergoing large deformations, are considered and developed. Since the governing non-linear equations usually becomes too complex to be handled analytically, the main focus has been on developing methods that can be incorporated into a numerical solution scheme, such as the finite element method. LÄS MER

  5. 25. Finite Element Procedures in Modelling the Dynamic Properties of Rubber

    Författare :Anders K Olsson; Byggnadsmekanik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; akustik; vibration and acoustic engineering; Materiallära; materialteknik; Mechanical engineering; hydraulics; vacuum technology; Material technology; dynamic; amplitude; frequency; Technological sciences; Teknik; FEM; rubber; vibrationer; vakuumteknik; Maskinteknik; hydraulik;

    Sammanfattning : Rubber is not only a non-linear elastic material, it is also dependent on strain rate, temperature and strain amplitude. The non-linear elastic property and the strain amplitude dependence give a non-linear dynamic behavior that is covered by the models suggested in this thesis. LÄS MER