Avancerad sökning

Hittade 4 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Inverse Modeling of Cloud – Aerosol Interactions

    Författare :Daniel Partridge; Johan Ström; Kari Lehtinen; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; stratocumulus; marine; cloud; aerosol; interactions; MCMC; inverse modeling; droplet closure; global sensitivity; Atmosphere and hydrosphere sciences; Atmosfärs- och hydrosfärsvetenskap; Applied Environmental Science; tillämpad miljövetenskap;

    Sammanfattning : The role of aerosols and clouds is one of the largest sources of uncertainty in understanding climate change. The primary scientific goal of this thesis is to improve the understanding of cloud-aerosol interactions by applying inverse modeling using Markov Chain Monte Carlo (MCMC) simulation. LÄS MER

  3. 2. On the Formation and Physical Behaviour of Exhaled Particles

    Författare :Helene Holmgren; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; breath hold; size distribution; deposition; relative humidity; tidal breathing; exhaled particles; airway closure; film droplet;

    Sammanfattning : Aerosol particles are generated in human airways and leave the body with exhaled air. The particles originate from the respiratory tract and contain non-volatile compoundsthat potentially may be used as biomarkers for various medical conditions. To utilise any information provided by the particles, they must be characterised. LÄS MER

  4. 3. Numerical Modelling of Fuel Injection and Stratified Turbulent Combustion in a Direct-Injection Spark-Ignition Engine Using an Open Source Code

    Författare :Chen Huang; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; hollow-cone spray; KHRT; liquid penetration; CFD; OpenFOAM; Flame Speed Closure FSC ; ignition delay; SMD; gasoline surrogate; laminar flame speed; presumed PDF; Spray-Guided Gasoline Direct Injection engine; chemical mechanism; modelling; premixed stratified turbulent combustion;

    Sammanfattning : Stringent regulations on the emission of pollutants, especially carbon dioxide (CO2), necessitate the development of advanced combustion technologies. Gasoline direct injection (GDI) into the combustion chamber of a Spark Ignition (SI) engine is a combustion strategy that is widely recognized as having the potential to improve fuel efficiency of internal combustion engines for passenger cars. LÄS MER

  5. 4. Turbulence modulation effects caused by small droplets using one-dimensional-turbulence

    Författare :Marco Fistler; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Multiphase Flow; Droplets; one-dimensional-turbulence ODT ; Turbulence;

    Sammanfattning : This thesis presents a stochastic model to study turbulence modulation effects on gas phases caused by small droplets or more generally speaking particles to achieve a better understanding about the physics and with the aim to provide data for a subgrid-scale (SGS) model for Large-eddy-simulations. The one-dimensional-turbulence (ODT) model addresses one of the major issues for multiphase flow simulations, namely computational costs. LÄS MER