Search for dissertations about: "High Karlovitz number"

Found 5 swedish dissertations containing the words High Karlovitz number.

2. 1. Experimental investigation of premixed ammonia combustion at high Karlovitz number conditions

   Author : Qingshuang Fan; Förbränningsfysik; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbulent premixed combustion; Ammonia flames; Laser diagnostics; Flame structure; High Karlovitz number; Turbulent burning velocity; Fysicumarkivet A:2021:Fan;

   Abstract : This thesis aims to acquire deep knowledge on turbulent premixed combustion at high Karlovitz (Ka) number conditions with the help of laser-based diagnostic measurements.Considering that ammonia (NH3), as a carbon-free energy carrier, is a promising candidate for replacing conventional fossil fuels in the future, all the investigations in this work were carried out on ammonia/air premixed flames. READ MORE

4. 2. Detailed Numerical Simulations of Turbulent Premixed Flames at Moderate and High Karlovitz Numbers

   Author : Henning Carlsson; Strömningsteknik; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Direct numerical simulation; Large eddy simulation; Turbulent premixed combustion; Flow-flame interaction; High Karlovitz number;

   Abstract : In generally accepted and applied flamelet combustion models, a turbulent flame is mainly assumed distorted by the large-scale turbulence eddies, whereas small-scale turbulence effects on the local flamelet structures are neglected. However, in a lot of industrial applications rather high turbulent intensities are often imposed, which induce turbulence scales at ranges smaller than the flame thickness. READ MORE

5. 3. Direct numerical simulation of turbulent premixed flames at high Karlovitz numbers: structure and modelling

   Author : Thommie Nilsson; Strömningsteknik; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Direct numerical simulation; Computational fluid dynamics; Combustion model; Premixed flame; Turbulence; Karlovitz number;

   Abstract : There has been recent increased interest in premixed flames and in particular for use in gas turbines for power generation. This is a development that follows from increasing demands for high efficiency and low emissions of NOx, which can be achieved by using premixed flames and lean pre-heated mixtures, often close to the lean flammability limit. READ MORE

6. 4. Development and application of laser diagnostics - from laboratory devices towards practical combustion engines

   Author : Zhenkan Wang; Förbränningsfysik; []
   Keywords : Combustion diagnostics; Laser induced fluorescence LIF ; Ultra-high-speed; Burst-mode laser; Ballistic imaging; Particle imaging velocimetry; Laser Doppler anemometry; Turbulent premixed combustion; Plasma; Internal combustion engine; Partially premixed combustion PPC ; Auto-ignition; OH radical; CH2O formaldehyde ; Fysicumarkivet A:2018:Wang;

   Abstract : For many decades, research work on combustion has been focused on improving combustion efficiency and reducing harmful emissions. Laser diagnostics is one of the best ways to investigate the combustion process and emission formation as it is non-intrusive and it has high spatiotemporal resolution. READ MORE

7. 5. Direct Numerical Simulation and Modelling Study of the Structures and Propagation of Partially Premixed Turbulent Flames

   Author : Vivianne Holmen; Strömningsteknik; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Abstract : Turbulent partially premixed flames are found in common combustion applications, such as the lifted jet flames in diesel engines. There is less theory surrounding the structure and propagation of turbulent partially premixed flames than for classical premixed flames and diffusion flames, especially in regards to modelling. READ MORE