Search for dissertations about: "Exhaust gases"

Showing result 6 - 10 of 74 swedish dissertations containing the words Exhaust gases.

  2. 6. Computational Aeroacoustics Based on Large Eddy Simulation and Acoustic Analogies

    Author : Mihai Mihaescu; Laszlo Fuchs; Strömningsteknik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Mechanical engineering; hydraulics; plasma; Technological sciences; Teknik; fluiddynamik; plasmas; Gaser; fluid dynamics; Gases; Inhomogeneous Wave Equation; Acoustic Boundary Conditions; Acoustic Source Terms; LES; Computational Aeroacoustics; Turbulent Flows; vacuum technology; vibration and acoustic engineering; Maskinteknik; hydraulik; vakuumteknik; vibrationer; akustik; Computational Aeroacoustics;

    Abstract : The thesis presents a numerical method developed by the author and its applications for computing the generated sound by an unsteady flow field and its propagation. The full equations of motion for compressible and unsteady flows describe both flow field and sound generation and propagation. READ MORE

  4. 7. Studies of MISiC-FET sensors for car exhaust gas monitoring

    Author : Helena Wingbrant; Anita Lloyd Spetz; Martin Eickhoff; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; field effect sensor; gas detection; selective catalytic reduction; lambda; cold start; ammonia; silicon carbide; engine exhaust; Physics; Fysik;

    Abstract : The increasing size of the car fleet makes it important to find ways of lowering the amounts of pollutants from each individual diesel or gasoline engine to almost zero levels. The pollutants from these engines predominantly originate from emissions at cold start, in the case when gasoline is utilized, and high NOx emissions and particulates from diesel engines. READ MORE

  5. 8. Flow Maldistribution in Exhaust Aftertreatment Systems - Numerical Simulations

    Author : Pratheeba Chanda Nagarajan; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Catalyst; Flow maldistribution; Transient; CFD Simulations; Reactive flows; Uniformity Index; Exhaust AfterTreatment Systems;

    Abstract : To comply with the stringent emission norms under every driving condition, including the coldstart conditions and Real Driving Emissions (RDE) tests, accurate models that capture the spatial and temporal variation of flow distribution information in Exhaust AfterTreatment Systems (EATS) are required. This study is aimed at characterizing and quantifying flow distribution in EATS under transient conditions with realistic geometry that illustrates the complex nature of the flow conditions. READ MORE

  6. 9. Development of a ferritic ductile cast iron for improved life in exhaust applications

    Author : Madeleine Ekström; Stefan Jonsson; Pamela Henderson; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Material development; SiMo51; HK30; exhaust manifolds; high-temperature corrosion; high-temperature low-cycle fatigue;

    Abstract : Due to coming emission legislations, the temperature is expected to increase in heavy-duty diesel engines, specifically in the hot-end of the exhaust system affecting components, such as exhaust- and turbo manifolds. Since the current material in the turbo manifold, a ductile cast iron named SiMo51, is operating close to its limits there is a need for material development in order to maintain a high durability of these components. READ MORE

  7. 10. Oxidation and corrosion fatigue aspects of cast exhaust manifolds

    Author : Madeleine Ekström; Stefan Jonsson; Ulf Olofsson; Babette Tonn; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; cast exhaust manifolds; high-temperature corrosion; high-temperature low-cycle fatigue; high-temperature corrosion fatigue; ductile cast irons; cast stainless steel; Materials Science and Engineering; Teknisk materialvetenskap;

    Abstract : Emission regulations for heavy-duty diesel engines are becoming increasingly restrictive to limit the environmental impacts of exhaust gases and particles. Increasing the specific power output of diesel engines would improve fuel efficiency and greatly reduce emissions, but these changes could lead to increased exhaust gas temperature, increasing demands on the exhaust manifold material. READ MORE