Search for dissertations about: "DEPENDENT MASS-LOSS"

Showing result 1 - 5 of 7 swedish dissertations containing the words DEPENDENT MASS-LOSS.

  1. 1. A Study of Grain Drift in C Stars : Theoretical Modeling of Dust-Driven Winds in Carbon-Rich Pulsating Giant Stars

    Author : Christer Sandin; Susanne Höfner; Bengt Gustafsson; Lee Anne Willson; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Astronomy; hydrodynamics; radiative transfer; instabilities; dust formation; stars: AGB and post-AGB; stars: mass-loss; stars: variables: general; Astronomi; Astronomy and astrophysics; Astronomi och astrofysik; Theoretical Astrophysics; teoretisk astrofysik;

    Abstract : A major fraction of stars will pass through a short period of dramatic events in their final evolutionary stage. Low- to intermediate-mass stars, studied here, are stripped of their outer parts in a slow massive wind. This mass loss reshapes both the star and the surrounding medium. READ MORE

  2. 2. Modelling the Winds from Carbon Rich AGB Stars : Implications for Stellar Evolution and the Chemical Evolution of Galaxies

    Author : Lars Mattsson; Uppsala universitet; []
    Keywords : ;

    Abstract : Stars on the AGB are known to lose mass at high rates (10-8 - 10-4 Msun/yr) through slow winds (20 km/s), enriching the inter stellar medium with newly synthesised elements. We explore how the mass loss for C-rich AGB stars depends on the basic stellar parameters by computing a large grid of wind models. READ MORE

  3. 3. Limiting conditions for a sustained flame over condensed fuels : Analysis by experiments and stagnant layer theory

    Author : Frida Vermina Plathner; Avdelningen för Brandteknik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Critical mass flux; diffusion flame; extinction; sustained ignition; chemical heat of combustion; Convective heat transfer coefficient; external heat flux;

    Abstract : Ignition and extinction characteristics of a material determine whether a fire will be initiated and grow. In fire safety engineering, where modellers deal with a multitude of materials, simplified thresholds are commonly used to determine when ignition and extinction occur. READ MORE

  4. 4. Determination of Material Properties for Fire Modelling

    Author : Ulf Göransson; Avdelningen för Brandteknik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Material properties; Material degradation; Measurements; Fire test data; Byggnadsteknik; Building construction; Teknik; Technological sciences; Fire; Surface temperature; Mathematical modelling;

    Abstract : Fire and flame spread are very complex phenomenon to study. Several aspects need to be considered and treated. In order to be able to do a correct analysis of the flame spread phenomenon, which is necessary to be able to predict flame spread, knowledge of material properties are needed. Material properties can be obtained in different ways. READ MORE

  5. 5. X-ray emission from supernova shock waves

    Author : Tanja Nymark; Claes Fransson; Cecilia Kozma; Jacco Vink; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Astronomy and astrophysics; Astronomi och astrofysik; Astronomy; astronomi;

    Abstract : A theoretical study of the interaction between supernovae and their surroundings is presented.Supernovae are the endpoint of the life of massive stars, and are the dominant contributors to the chemical evolution of the Universe. During its life a massive star greatly modifies its environment. READ MORE