Sökning: "Johan Andrae"

Hittade 3 avhandlingar innehållade orden Johan Andrae.

1. 1. Numerical Studies of Wall Effects of Laminar Flames

   Författare :Johan Andrae; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; wall effects; laminar premixed flames; Chemkin; boundary layer flow; Chemical engineering; Kemiteknik;

   Sammanfattning : Numerical simulations have been done with the CHEMKINsoftware to study different aspects of wall effects in thecombustion of lean, laminar and premixed flames in anaxisymmetric boundary-layer flow. The importance of the chemical wall effects compared to thethermal wall effects caused by the development of the thermaland velocity boundary layer has been investigated in thereaction zone by using different wall boundary conditions, walltemperatures and fuel/air ratios. LÄS MER

3. 2. 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

4. 3. Kinetic modelling of autoignition phenomena

   Författare :David Johansson; Pehr Björnbom; Johan Andrae; Ulf Henriksson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Chemical engineering; Kemiteknik;

   Sammanfattning : To fully understand the elementary reactions behind the ignition of automotive fuels the interaction between the fuel components must be known. The ignition initiation is most often caused by loss of an H radical from a reactive fuel molecule, for example n-heptane. The formed alkyl radical is prone to react with oxygen under lean conditions. LÄS MER