Sökning: "lean burn"

Visar resultat 16 - 20 av 36 avhandlingar innehållade orden lean burn.

  1. 16. Fundamental Studies of Catalytic NOx Removal - Micro Kinetic Modelling, Monte Carlo Simulations and Flow Reactor Experiments

    Författare :Louise Olsson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NO oxidation; Monte Carlo simulations; platinum oxide; kinetic modelling; NOx storage; barium oxide; environmental catalysis; NOx removal; platinum; flow reactor measurements;

    Sammanfattning : It is essential to decrease the CO2 emissions from vehicles, since CO2 is a greenhouse gas. One way to improve fuel economy and decrease CO2 emissions, is to run the engine with oxygen excess, so-called lean-burn operation. However, a major problem here is the reduction of the NOx in a lean atmosphere. LÄS MER

  3. 17. Mitigating Knock in Heavy Duty Spark Ignition Engines : Experiments and simulations of diluted ethanol and methanol combustion

    Författare :Senthil Krishnan Mahendar; Anders Christiansen Erlandsson; Christer Spiegelberg; James Szybist; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Ethanol; Methanol; Dilution; Spark Ignition; Miller Timing; Machine Design; Maskinkonstruktion;

    Sammanfattning : To effectively reduce fossil fuel dependence in the transport sector, an unprecedented increase in renewable fuel production is required. Short chain alcohols, such as ethanol and methanol, are well placed as they can be produced in a variety of renewable pathways from most carbon sources. LÄS MER

  4. 18. An Experimental Study of a Spark-assisted

    Författare :Andreas Berntsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : Future requirements for reductions in fuel consumption and emissions from ground vehicles might be met by using the HCCI combustion concept, in which a more or less homogenous air fuel mixture is compressed to auto-ignition. This consumes less fuel than normal SI combustion and its ability to burn lean mixtures at low temperatures has a positive impact on exhaust emissions. LÄS MER

  5. 19. Studies of hydrocarbon-assisted selective catalytic reduction of nitrogen oxides - DME as reductant and reaction mechanism over silver/alumina

    Författare :Stefanie Tamm; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ZSM-5; NCO; HC-SCR; Dimethyl ether; reaction mechanism; silver alumina;

    Sammanfattning : Increasing amounts of carbon dioxide are attaining worldwide growing attention as one probable cause for global warming. Together with the expected peak in oil production and an increasing oil demand, this results in a greater interest in more fuel effective lean burn engines (i.e. operation with excess oxygen). LÄS MER

  7. 20. Super-grid Linear Eddy Model (SG-LEM): Efficient mode- and regime-independent combustion closure for Large Eddy Simulation (LES)

    Författare :Abhilash Murlidharan Menon; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Large Eddy Simulation; Mapping-closure; Lagrangian splicing; Mesh coarse-graining.; Linear Eddy Model;

    Sammanfattning : Next-generation combustion technology such as ‘lean burn’ and HCCI (Homogeneous Charge Compression Ignition) present new challenges for  combustion modelling. The presence of locally varying combustion modes (premixed vs. non-premixed) and regimes (fast/non-fast chemistry vs. LÄS MER