Sökning: "Premixed flame"

Visar resultat 1 - 5 av 94 avhandlingar innehållade orden Premixed flame.

1. 1. Flame Dynamics and Deflagration-to-Detonation Transition

   Författare :Damir Valiev; Börje Johansson; R. J. M. (Rob) Bastiaans; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; flame; premixed; instability; fractal; deflagration; detonation; DDT; simulation; Physics; Fysik;

   Sammanfattning : Various premixed flame phenomena are studied by means of direct numerical simulations of the complete system of hydrodynamic equations. Rigorous study of flame dynamics is essential for all premixed combustion problems where multidimensional effects cannot be disregarded.The present thesis consists of six parts. LÄS MER

3. 2. The role of Landau-Darrieus instability in flame dynamics and deflagration-to-detonation transition

   Författare :Damir Valiev; Börje Johansson; Vladimir Karlin; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; flame; premixed; instability; front; Landau; Darrieus; fractal; freely; deflagration; detonation; transition; DDT; modeling; simulation; Other materials science; Övrig teknisk materialvetenskap;

   Sammanfattning : The role of intrinsic hydrodynamic instability of the premixed flame (known as Landau-Darrieus instability) in various flame phenomena is studied by means of direct numerical simulations of the complete system of hydrodynamic equations. Rigorous study of flame dynamics and effect of Landau-Darrieus instability is essential for all premixed combustion problems where multidimensional effects cannot be disregarded. LÄS MER

4. 3. Modelling effects of flame development on stationary and oscillating premixed turbulent combustion

   Författare :Pratap Sathiah; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; flame development; Keywords: Premixed turbulent flame; Flame Speed Closure model;

   Sammanfattning : The vast majority of contemporary models of premixed turbulent flames applied to multi-dimensional RANS numerical simulations of combustion in gas turbine engines and aero-engine afterburners focus on fully-developed flames, characterized by fully-developed turbulent diffusivity, thickness, and burning velocity. However, abundant experimental data obtained from statistically stationary premixed flames clearly show that a typical turbulent flame develops as it is convected by mean flow from a stabilization zone. LÄS MER

5. 4. Experimental and Numerical Investigations of Flames Stabilized by Swirl Flow and Bluff-body:Flame Structures and Flame Instabilities

   Författare :Yiheng Tong; Kraftverksteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Flame structures; Flame instabilities; Blowout limits; Flashback; Swirl Flow; Bluff-body; Chemiluminescence; PIV;

   Sammanfattning : Combustion and its control are essential to our existence on this planet since we knew it. Nowadays, the largest share of the world’s electricity and most of our transportation systems are powered by combustion. In addition, industrial processes also rely heavily upon combustion. LÄS MER

7. 5. Wall Related Lean Premixed Combustion Modeled with Complex Chemistry

   Författare :Johan Andrae; KTH; []
   Nyckelord :Wall effects; premixed flames; flame quenching; numerical modeling; chemkin; boundary layer approximation; gasified biomass; fuel-NOx; hybrid catalytic combustor.; NATURAL SCIENCES; NATURVETENSKAP;

   Sammanfattning : Increased knowledge into the physics and chemistrycontrolling emissions from flame-surface interactions shouldhelp in the design of combustion engines featuring improvedfuel economy and reduced emissions. The overall aim of this work has been to obtain afundamental understanding of wall-related, premixed combustionusing numerical modeling with detailed chemical kinetics. LÄS MER