Sökning: "velocity fluctuations"

Visar resultat 1 - 5 av 76 avhandlingar innehållade orden velocity fluctuations.

  1. 1. Mesoscopic analysis of instantaneous velocities of particles in a circulating fluidized bed using a phase Doppler particle analyzer

    Författare :Tobias Bergenblock; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; velocity fluctuations; pressure fluctuations; scales; particle group; circulating fluidized bed; phase doppler particle analyzer;

    Sammanfattning : .... LÄS MER

  3. 2. Development of an integrated neutronic/thermal-hydraulic tool for estimating fluctuations in PWRs

    Författare :Viktor Larsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Diffusion theory; Fluctuations; Neutron noise; Coupled calculations; P1 theory Analytical Nodal Method;

    Sammanfattning : Monitoring and diagnostics of a reactor core at a given state is very important for detecting potential problems and anomalies at an early stage. Several methods exist for these purposes, but the majority of them require a disruption of the plant operation, e.g. by shut-down or by perturbation of the system. LÄS MER

  4. 3. On some positive effects of swirling flow for the continuous cast mould billets

    Författare :Shavkat Kholmatov; Pär Jönsson; Simon Lille; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; swirling flow; round mould; divergent angle; aspect ratio; temperature distribution; velocity fluctuations; continuous casting of steel; mathematical modeling; CFD; Metallurgical process engineering; Metallurgisk processteknik;

    Sammanfattning : Continuous caster moulds are the last and most important stage in the steelmaking process, where inclusions can either be generated or removed. With increasing casting speed using conventional immersion nozzles critical problems, such as unstable bulk mould flow have been noticed. LÄS MER

  5. 4. Fluid Dynamics of the Bottom Bed of Circulating Fluidized Bed Boilers

    Författare :Anders Svensson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fluidized beds; circulating fluidized bed boilers; fluctuations; fluidization regimes; bottom bed; bed porosity; fluid dynamics; bubbling beds; circulating fluidized beds; non-slugging; bed expansion; particle concentration;

    Sammanfattning : The fluid dynamic conditions in the furnace of a fluidized bed boiler influence the combustion and the production of harmful emissions. A substantial amount of the bed material in a circulating fluidized bed (CFB) boiler is present as a dense bubbling bottom bed. LÄS MER

  7. 5. Plasma environment of an intermediately active comet : Evolution and dynamics observed by ESA's Rosetta spacecraft at 67P/Churyumov-Gerasimenko

    Författare :Elias Odelstad; Anders Eriksson; Andrew Coates; Uppsala universitet; []
    Nyckelord :Rosetta; comet; 67P; RPC-LAP; RPC-MIP; RPC-ICA; RPC-MAG; ROSINA-COPS; Langmuir probe; spacecraft potential; plasma; Churyumov-Gerasimenko; ion composition analyzer; diamagnetic cavity; ion velocity; electron temperature; ion-neutral drag; collisional coupling; wake effects; filamentation; electron cooling; plasma waves; hybrid waves; Bernstein waves; minimum variance; polarization; wavelet; density fluctuations; magnetic field oscillations; drift-cyclotron instability; asymmetric plasma and magnetic field enhancements; Fysik med inriktning mot rymd- och plasmafysik; Physics with specialization in Space and Plasma Physics;

    Sammanfattning : The subject of this thesis is the evolution and dynamics of the plasma environment of a moderately active comet before, during and after its closest approach to the Sun. For over 2 years in 2014-2016, the European Space Agency’s Rosetta spacecraft followed the comet 67P/Churyumov-Gerasimenko at distances typically between a few tens and a few hundred kilometers from the nucleus, the longest and closest inspection of a comet ever made. LÄS MER