Sökning: "hydraulik"

Visar resultat 6 - 10 av 54 avhandlingar innehållade ordet hydraulik.

  1. 6. Numerical Modelling of Fuel Sprays

    Författare :Christer Bergström; Strömningsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vibration and acoustic engineering; vacuum technology; hydraulics; Mechanical engineering; Gas turbine.; Temperature fluctuations. Diesel engine; Counter rotating Vortex Pair; CVP; Large Eddy Simulation; Droplet Evaporation; Turbulent flows; LES; Spray; Modelling; Break-up; Maskinteknik; hydraulik; vakuumteknik; vibrationer; akustik; Carbochemistry; petrochemistry; fuels and explosives technology; Petrokemi; bränslen; sprängämnen;

    Sammanfattning : The way the fuel is introduced into the combustion chamber is one of the most important parameters for the power output and the generation of emissions in the combustion of liquid fuels. The interaction beween the turbulent gas flow field and the liquid fuel droplets, the vaporisation of them and the mixing of the gaseous fuel with the ambient air that are vital parameters in the combustion process. LÄS MER

  3. 7. Harmonic Mitigation in Traction Drives

    Författare :Hans Bängtsson; Industriell elektroteknik och automation; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; hydraulics; Mechanical engineering; converter; line interference; track circuit; Railway signalling system; vacuum technology; vibration and acoustic engineering; Maskinteknik; hydraulik; vakuumteknik; vibrationer; akustik;

    Sammanfattning : In railway traffic the low friction between wheel and rail causes long braking distances, normally much longer than the sight distance of the driver, i.e. if the driver starts the braking when a problem on the track is discovered, it might be too late to brake the train. Therefore, safe railway traffic can not only rely on the driver. LÄS MER

  4. 8. Modelling of compaction of metal powder and damage accum ulation due to fatigue in powder materials

    Författare :Joakim Cedergren; Mekanik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; hydraulik; vakuumteknik; vibrationer; akustik; Maskinteknik; hydraulics; Mechanical engineering; friction; FEM; numerical modelling; continuum mechanics; fatigue loading; powder compaction; vacuum technology; vibration and acoustic engineering;

    Sammanfattning : This thesis addresses powder manufactured (P/M) components, with special attention to the compaction process and to the sensitivity to damage accumulation due to fatigue within powder compacted specimens. Three dimensional simulations of the compaction process have been performed, using an explicit dynamic dilatant finite strain finite element code supplemented with the effects from contact friction within the die, modelled by Coulomb friction. LÄS MER

  5. 9. Structure-acoustic analysis; finite element modelling and reduction methods

    Författare :Peter Davidsson; Byggnadsmekanik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Mechanical engineering; hydraulics; vacuum technology; vibration and acoustic engineering; Maskinteknik; hydraulik; vakuumteknik; vibrationer; akustik; low frequency range; building acoustics; lightweight structures; porous materials; modal reduction; substructuring; finite element analysis; structural acoustics; vibroacoustics; Structural dynamics;

    Sammanfattning : This thesis investigates structure-acoustic systems by use of finite element analysis. The systems studied here are limited to those that consist of an enclosed acoustic fluid cavity, which is coupled to a flexible structure and/or a porous sound absorbing material domain. LÄS MER

  7. 10. 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