Sökning: "runaway"

Visar resultat 16 - 20 av 40 avhandlingar innehållade ordet runaway.

1. 16. The galactic scale impact of feedback from individual stars

   Författare :Eric Andersson; Astronomi - Genomgår omorganisation; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; galaxies; galaxy evolution; galactic winds; interstellar medium; star formation; stellar feedback; runaway stars; numerical modelling;

   Sammanfattning : Feedback from stars is essential for the formation and evolution of galaxies. It is an energy source that drives gas motions and chemically enriches the galaxy by supplying metals. Without this stellar feedback, numerical galaxy simulations result in galaxies with little resemblance to those observed in our Universe. LÄS MER

3. 17. Stability and Statistical Analysis of Transient Waves in Fusion Plasmas

   Författare :Gergö Pokol; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; short-time Fourier transform; transient MHD mode; wavelet transform; quasi-linear diffusion; runaway electron; transient transport; stellarator; tokamak disruption; fusion plasma physics; whistler wave;

   Sammanfattning : Thermonuclear energy generation in magnetically confined plasmas offers an appealing energy source for coming generations. Some of the still unsolved problems in fusion plasma physics involve plasma transport and stability of plasma waves. Two such problems are addressed in the present thesis. LÄS MER

4. 18. Assessment of safety characteristics for Li-ion battery cells by abuse testing

   Författare :Carl Fredrik Larsson; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; overcharge; Lithium-ion; toxic gases; abuse test; thermal runaway; short circuit; safety; battery; fire;

   Sammanfattning : Despite the many advantages with lithium-ion batteries there can be disadvantages in form of safetyissues. In an abuse situation a Li-ion cell can undergo a thermal runaway releasing excessive heat,flammable and toxic gas emissions and eventually accompanied by dissembling/explosion and fire. LÄS MER

5. 19. Disruption Mitigation in Tokamaks with Massive Material Injection

   Författare :Oskar Vallhagen; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; shattered pellet injection; fusion plasma; disruption mitigation; runaway electron;

   Sammanfattning : The sudden loss of confinement of the energy content of fusion plasmas in off-normal events, called disruptions, is among the most severe threats to the future of fusion energy based on the tokamak design. An efficient disruption mitigation system will therefore be of utmost importance for future large, high-current devices such as ITER. LÄS MER

7. 20. Lithium-ion Battery Safety - Assessment by Abuse Testing, Fluoride Gas Emissions and Fire Propagation

   Författare :Carl Fredrik Larsson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fire; thermal runaway; gas emission; gas explosion; propagation; safety; abuse testing; Lithium-ion; cell case explosion; hydrogen fluoride;

   Sammanfattning : Lithium-ion batteries offer high energy and power densities as well as long life time but have a more narrow stability window compared to other battery types and contain reactive and flammable materials. In case of overheating the battery cell can release gas (vent) and, at temperatures of about 150-200 °C, a so called thermal runaway can occur, that is a rapid self-heated temperature increase which is typically accompanied with a large release of smoke and gas, fire and a potential cell case explosion or gas explosion. LÄS MER