A comparison of the multicomponent model and the mixture averaged approximation
(2014) FYSM31 20141Department of Physics
Combustion Physics
 Abstract
 In this work the major models for calculating diffusion in simulations of a laminar premixed hydrogen flame, the mixture averaged approximation and the multicomponent model, are explained and compared. This is done in order to see if the accuracy gained in implementing the multicomponent model is enough to warrant the increased workload the transition will cause.
The models are used to calculate the mean flame speed for a hydrogen flame, as that is the one most easily measured in experiments. But the results are inconclusive in comparison with experiment, since thermal diffusion was not implemented. Still, it does show a clear distinction between the results produced by the two models, as the mixture averaged model gives the flame... (More)  In this work the major models for calculating diffusion in simulations of a laminar premixed hydrogen flame, the mixture averaged approximation and the multicomponent model, are explained and compared. This is done in order to see if the accuracy gained in implementing the multicomponent model is enough to warrant the increased workload the transition will cause.
The models are used to calculate the mean flame speed for a hydrogen flame, as that is the one most easily measured in experiments. But the results are inconclusive in comparison with experiment, since thermal diffusion was not implemented. Still, it does show a clear distinction between the results produced by the two models, as the mixture averaged model gives the flame speed as 239 cm/s while the multicomponent gives it as 250 cm/s, for a stoichiometric hydrogen flame with standard temperature and pressure.
The calculation time is also significantly different, as the multicomponent calculation took 42 minutes, while the mixture averaged calculations only took 17 minutes. Worth noting is that the mixture averaged model was heavily optimized, which explains some of the difference. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/studentpapers/record/4331903
 author
 Torstensson, Martin ^{LU}
 supervisor

 Anders Borg
 Johan Zetterberg ^{LU}
 organization
 course
 FYSM31 20141
 year
 2014
 type
 H1  Master's Degree (One Year)
 subject
 keywords
 Combustion physics, computational physics, multicomponent model, mixture averaged approximation
 language
 English
 id
 4331903
 date added to LUP
 20140227 11:53:16
 date last changed
 20141022 10:19:22
@misc{4331903, abstract = {In this work the major models for calculating diffusion in simulations of a laminar premixed hydrogen flame, the mixture averaged approximation and the multicomponent model, are explained and compared. This is done in order to see if the accuracy gained in implementing the multicomponent model is enough to warrant the increased workload the transition will cause. The models are used to calculate the mean flame speed for a hydrogen flame, as that is the one most easily measured in experiments. But the results are inconclusive in comparison with experiment, since thermal diffusion was not implemented. Still, it does show a clear distinction between the results produced by the two models, as the mixture averaged model gives the flame speed as 239 cm/s while the multicomponent gives it as 250 cm/s, for a stoichiometric hydrogen flame with standard temperature and pressure. The calculation time is also significantly different, as the multicomponent calculation took 42 minutes, while the mixture averaged calculations only took 17 minutes. Worth noting is that the mixture averaged model was heavily optimized, which explains some of the difference.}, author = {Torstensson, Martin}, keyword = {Combustion physics,computational physics,multicomponent model,mixture averaged approximation}, language = {eng}, note = {Student Paper}, title = {A comparison of the multicomponent model and the mixture averaged approximation}, year = {2014}, }