Sökning: "process zone"

Visar resultat 21 - 25 av 409 avhandlingar innehållade orden process zone.

1. 21. Methanation of biosyngas in a fluidized bed reactor

   Författare :Martin Seemann; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ENERGY TECHNOLOGY; REGENERATIVE ENERGIES; GASIFICATION OF WOOD; FLUIDIZED BED PROCESSES; CHEMICAL ENGINEERING; FUEL TECHNOLOGY; ALTERNATIVE ENERGIES; METHANATION OF HYDROGEN-CARBONMONOXIDE MIXTURES; SYNTHETIC FUELS; NATURAL GAS; BIOGASES;

   Sammanfattning : Rising prices for fossil fuels and concerns over the climate change increase the interest in renewable energies. Synthetic natural gas (SNG) can be an option, filling the request for alternatives in the transportation sector, where the dependence on the oil is very strong. LÄS MER

3. 22. Physics of Aftershocks in the South Iceland Seismic Zone : Insights into the earthquake process from statistics and numerical modelling of aftershock sequences

   Författare :Mattias Lindman; Roland Roberts; Björn Lund; David Marsan; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Earthquake processes; Aftershocks; Physics of aftershocks; Omori law; Postseismic processes; Pore pressure diffusion; Poroelasticity; Statistical seismology; Self-organised criticality; Interevent time distributions; Waiting time distributions; Geophysics; Geofysik;

   Sammanfattning : In seismology, an important goal is to attain a better understanding of the earthquake process. In this study of the physics of aftershock generation, I couple statistical analysis with modelling of physical processes in the postseismic period. LÄS MER

4. 23. Microfluidic Hydrodynamic of Gas-Liquid flow in Single Microchannel and Porous Media with Microchannel Network

   Författare :Shuo Yang; NanoLund: Centre for Nanoscience; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; mass transfer; slug flow; porous media; interficial instability; fingering displacement;

   Sammanfattning : In this thesis, a microfluidics platform with high-speed imaging system was built to investigate gas-liquid flow in single microchannel and interfacial instability in porous media with microchannel network:The mass transfer of slug flow in the rectangular and square microchannels was experimentally studied by using water as liquid phase and CO2 as gas phase. Depending on flow rates, flow patterns including slug flow, bubbly flow, and annular flow were observed in rectangular and square microchannels. LÄS MER

5. 24. Fundamental studies of catalytic systems for diesel emission control

   Författare :Xavier Auvray; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NH3 SCR; NO oxidation; sulfur; hysteresis; kinetic modeling; SpaciMS; catalyst acidity; DOC; aging; Pt Al2O3;

   Sammanfattning : Due to global lean exhaust gas and new emission regulations, exhaust aftertreatment systems of diesel engines are more and more sophisticated and composed of a series of catalytic units. In the present work, two of these catalytic systems were studied with different approach. LÄS MER

7. 25. Combustion, Fluid Dynamics and Heat Transfer in Oxy-fuel and Air-Fired CFB boilers

   Författare :Sadegh Seddighi; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Carbon Capture and Storage; Combustion; Circulating Fluidized Bed; Oxy-Fuel; Multi-Phase Reacting Flow; Boiler Design; Emission; Fluid Dynamics; Heat Transfer;

   Sammanfattning : The studies described in this thesis develop and encode modeling tools for the design and scale-up of oxy-fuel circulating fluidized bed (CFB) boilers across a wide range of operational conditions. The modeling comprises fluid dynamics, combustion, and heat transfer and uses expressions that are proposed in this work or derived from the literature, together with experimental data obtained under both oxy-fuel-fired and air-fired conditions. LÄS MER