Sökning: "vibration and acoustic engineering"

Visar resultat 21 - 25 av 87 avhandlingar innehållade orden vibration and acoustic engineering.

  1. 21. Characterization of the Homogeneous Charge Compression Ignition Combustion Process

    Författare :Anders Hultqvist; Förbränningsmotorer; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; akustik; Motors and propulsion systems; Motorer; framdrivningssystem; Termisk teknik; termodynamik; Thermal engineering; applied thermodynamics; vakuumteknik; hydraulik; Maskinteknik; vibration and acoustic engineering; hydraulics; vacuum technology; ATAC; Mechanical engineering; MK; CAI; TS; MULDIC; PREDIC; HCCI; fuel tracer; combustion; injection; direct; port; engine; LDV; LIF; PLIF; vibrationer;

    Sammanfattning : The main objective of this project was to characterize the HCCI combustion process. Central parts in the project were the progress of the HCCI combustion process, the influence of charge homogeneity on the combustion process and sources of UHC and CO emissions in HCCI combustion. LÄS MER

  3. 22. Analyses of Spur and Helical Gears

    Författare :Anette Andersson; Maskinelement; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vacuum technology; vibration and acoustic engineering; Maskinteknik; hydraulik; vakuumteknik; vibrationer; akustik; hydraulics; Teknik; Mechanical engineering; Technological sciences; misalignment; contact ratio; load distribution; transmission error; tooth contact analysis;

    Sammanfattning : The thesis contains three papers that comprise studies of the dynamic behaviour of involute spur and helical gears, and one paper that describes a method to determine the influence of misalignment on the static helical gear tooth stress. In the first study, the influence of the contact ratio on the dynamic response of a spur gear was examined. LÄS MER

  4. 23. Mechanical Analysis of Lubrication and Lubricants

    Författare :Jonas Ståhl; Maskinelement; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vakuumteknik; vibrationer; Maskinteknik; hydraulik; akustik; Mechanical engineering; hydraulics; vacuum technology; vibration and acoustic engineering;

    Sammanfattning : This thesis comprises three different topics within the field of tribology. First, design functions for analyses of slider bearings are developed. Second, a lubricant model applied to elastohydrodynamically lubricated (EHL) line contacts considering wall-slip is presented. LÄS MER

  5. 24. 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

  7. 25. In-Cylinder Fluid Flow, Fuel Preparation and Combustion in SI Engines - Application of Optical Diagnostics

    Författare :Martin Ekenberg; Förbränningsmotorer; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Laserteknik; vakuumteknik; vibrationer; akustik; Motors and propulsion systems; Motorer; hydraulik; Maskinteknik; PIV; vibration and acoustic engineering; hydraulics; vacuum technology; Mechanical engineering; framdrivningssystem; Laser technology;

    Sammanfattning : In this thesis laser-based measurements of in-cylinder flow and fuel concentrations in two stroke and direct injected four-stroke engines are presented. The major problem with the carburetted two-stroke engine is the short-circuiting of fuel that occurs during the scavenging phase. This leads to large emissions of unburned hydrocarbons. LÄS MER