Search for dissertations about: "Complex Turbulent Flows"

Showing result 16 - 20 of 66 swedish dissertations containing the words Complex Turbulent Flows.

2. 16. Numerical Modelling of Fuel Sprays

   Author : Christer Bergström; Strömningsteknik; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vibration and acoustic engineering; vacuum technology; hydraulics; Mechanical engineering; Gas turbine.; Temperature fluctuations. Diesel engine; Counter rotating Vortex Pair; CVP; Large Eddy Simulation; Droplet Evaporation; Turbulent flows; LES; Spray; Modelling; Break-up; Maskinteknik; hydraulik; vakuumteknik; vibrationer; akustik; Carbochemistry; petrochemistry; fuels and explosives technology; Petrokemi; bränslen; sprängämnen;

   Abstract : The way the fuel is introduced into the combustion chamber is one of the most important parameters for the power output and the generation of emissions in the combustion of liquid fuels. The interaction beween the turbulent gas flow field and the liquid fuel droplets, the vaporisation of them and the mixing of the gaseous fuel with the ambient air that are vital parameters in the combustion process. READ MORE

4. 17. Simulation methods for hydropower flows : modeling and validation experiments

   Author : T. Fredrik Engström; Luleå tekniska universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Strömningslära; Fluid Mechanics;

   Abstract : My research project aims for more accurate modeling of the flow in hydropower plants. By accurate modeling, it is possible to try different modifications on existing plants in an affordable manner. Also, entirely new designs can be tested before realization. Hydropower delivers almost 50% of Sweden's electricity demand with a production of 74 TWh. READ MORE

5. 18. Large Eddy Simulation of Turbulent Flows in Combustor Related Geometries

   Author : Jessica Gullbrand; Institutionen för energivetenskaper; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Mechanical engineering; Energiforskning; Energy research; Cartesian grid; high order wall treatment; SGS models; turbulence; subgrid scale models; LES; Large Eddy Simulation; akustik; vibrationer; vakuumteknik; hydraulik; vibration and acoustic engineering; Maskinteknik; vacuum technology; hydraulics;

   Abstract : Numerical simulations using Large Eddy Simulation (LES) are applied to turbulent swirling flow fields. The swirling motion is often introduced into combustors to act as flame holders or enhance the mixing between species. Different turbulence models capture the swirling motion more or less accurately. READ MORE

6. 19. CFD Modelling of Hydrogen Rich Biomass Syngas Combustion

   Author : Nikolaos Papafilippou; Rikard Gebart; Kentaro Umeki; Muhammad Aqib Chishty; Christophe Duwig; Luleå tekniska universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; CFD; RANS; LES; FGM; Turbulent Combustion; Numerical Combustion; Swirling Flows; Gas Turbines; Biomass Syngas; Hydrogen; Energiteknik; Energy Engineering;

   Abstract : The loss of biodiversity, due to pollution and global warming, is more important and relevant now than it has ever been. Man made climate warming has its roots in the huge amount of CH4 and CO2 emissions, which have increased by 47% and 156% respectively since 1750. READ MORE

7. 20. Turbulence Modelling of Flows Related to Wall-Cooling Applications

   Author : Stefan Jansson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; low-Reynolds number models; second-order-moment closures; turbulent heat transfer; two-equation models; film-cooling; near-wall models; turbulence modelling;

   Abstract : Engineering flows are generally characterised by complex strain field and turbulence structure arising from a combination of shear, curvature, separation and recirculation etc. Under such flow conditions, transport by turbulent velocity fluctuations can make a significant contribution to the transport of momentum, heat and mass. READ MORE