Sökning: "gas bubbling"

Visar resultat 1 - 5 av 30 avhandlingar innehållade orden gas bubbling.

1. 1. Thermodynamics and Kinetics in Metallurgical Processes - with a Special Focus on Bubble Dynamics

   Författare :Yu Liu; Mikael Ersson; Pär Göran Jönsson; Bjoern Glaser; Joaquín B. Ordieres-Meré; Yogeshwar Sahai; Birgit Palm; Ville-Valtteri Visuri; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ladle; EAF; gas bubbling; physical modeling; mathematical modeling; thermodynamics; Skänkmetallurgi; EAF; gasbubblor; experimentell modellering; matematisk modellering; termodynamik; Teknisk materialvetenskap; Materials Science and Engineering; Metallurgical process science; Metallurgisk processvetenskap;

   Sammanfattning : Gas stirring is commonly used in the steelmaking processes to reinforce chemical reactions, kinetic transfer, and inclusion removal, etc. This dissertation concentrates on multiphase flows with gas bubbling to study fluid dynamics and thermodynamics in metallurgical processes. LÄS MER

3. 2. Heat and Mass Transfer to a Single Particle in Fluidized Bed

   Författare :Gennadij I. Palconok; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; mass transfer; turbulence; circulating fluidized beds; active particle; bubbling; heat; combustion; devolatilization;

   Sammanfattning : Heat and mass transfer to/from a single active particle in bubbling and circulating fluidized beds have been studied with application to fluidized bed combustion. A method of calculation of the heat and mass transfer coefficients in a bubbling fluidized bed (BFB) has been developed. LÄS MER

4. 3. SOLIDS MIXING IN BUBBLING FLUIDIZED BEDS

   Författare :Erik Sette; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fluid-dynamic scaling; Solids mixing; lateral dispersion; solids cross-flow;

   Sammanfattning : For solid fuels, thermochemical conversion processes such as combustion and gasification are especially suitable to be carried out in fluidized bed units because of the relatively high mixing rates, fuel flexibility and the possibility to use active bed material to enhance process efficiency. Mixing of fuel is important to ensure complete conversion and reduced emissions of unburnt material. LÄS MER

5. 4. A Numerical Study of the Fluid Dynamics of Bubbling Fluidized Beds

   Författare :Hans Enwald; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; validation; two-phase solver; multiblock; statistical bubble parameters; parallelization; bed expansion ratio; bubbling fluidized bed; two-fluid model;

   Sammanfattning : The two-fluid model was evaluated as a tool for predicting local flow behaviour in bubbling fluidized beds. A review is given of the two-fluid model approach for simulation of the flow in bubbling fluidized beds. LÄS MER

7. 5. Modelling and Simulation of Turbulent Gas-Solid Flows applied to Fluidization

   Författare :Eric Peirano; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Eulerian models; fluidization; two-fluid model; two-phase flow; granular flow theory; turbulence; fluidized beds; gas-solid flows;

   Sammanfattning : Modelling of gas-solid suspensions has been studied with emphasis on suitable closure laws. A study of characteristic time scales and energy dissipation mechanisms is made for the case of a simple shear flow. Applications of the modelling are presented in the form of simulation and validation of experiments in fluidized beds. LÄS MER