Sökning: "pool fire"

Visar resultat 1 - 5 av 8 avhandlingar innehållade orden pool fire.

  1. 1. Melt flow and surface stability effects on polymer flammability : A study on polystyrene, flexible polyurethane foam and polyolefin composites

    Författare :Roland H. Krämer; Ulf W. Gedde; Norman C. Billingham; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Melt; flow; dripping; collapse; combustion; pool fire; feed‐back; gasification; heat release; flammability; nanocomposites; molar mass; intumescence; polyurethane; Polymer chemistry; Polymerkemi;

    Sammanfattning : Our ability to accurately determine the flammability properties of polymers is hampered bythe erratic effects of deformation and liquid flow that occur during polymer combustion.This study aims to improve the understanding of such effects at several levels: The often obvious impact of melt flow on standardized flammability test methods forelectrical appliances is described to identify the need and to motivate others to worktowards an improved material characterization. LÄS MER

  3. 2. Numerical modeling of the coupled feedback between pool fires and their environment

    Författare :Jonathan Wahlqvist; Avdelningen för Brandteknik; []
    Nyckelord :;

    Sammanfattning : Computational fluid dynamics (CFD) is often used within performance based fire safety engineering and its use has increased as available computational power has increased. However, there is still a need to improve CFD modeling to push it beyond its current usage limitations. LÄS MER

  4. 3. Permafrost carbon in a changing Arctic : On periglacial landscape dynamics, organic matter characteristics, and the stability of a globally significant carbon pool

    Författare :Niels Weiss; Peter Kuhry; Duane Froese; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Permafrost; Carbon; Climate; Arctic; Soil; Organic Matter; Cryosphere; Geomorphology; Physical Geography; naturgeografi;

    Sammanfattning : Organic matter (OM) in arctic permafrost ground contains about twice as much carbon (C) as is currently present in the atmosphere. Climate change is particularly strong in the Arctic, and could cause a considerable part of the OM in permafrost to thaw out, decompose, and be released as greenhouse gases; further enhancing global warming. LÄS MER

  5. 4. Megaherbivores and Earth system functioning: Landscape-scale effects of white rhino loss on vegetation, fire and soil carbon dynamics

    Författare :Olli Hyvärinen; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Megaherbivores (> 1000 kg) have been suggested to strongly influence ecosystem functioning with consequences potentially scaling up to the global climate. However, due to poaching, we may lose some of the most vulnerable species at functional densities in the wild in the coming decades. LÄS MER

  7. 5. Spark Ignition Combustion of Direct Injected Alternative Fuels

    Författare :Lars Christian Riis Johansen; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; spark ignition; optical diagnostics; internal combustion engine; stratified combustion;

    Sammanfattning : Several technologies and modifications exist to increase the fuel efficiency of passenger vehicles in general and spark ignition engines in particular. Combining a spark ignition engine with an electric drive system in hybrid powertrain and thermodynamic cycle improvements are two such approaches with the potential to greatly reduce fuel consumption. LÄS MER