Analyses théorique, numérique et expérimentale de la détermination de la vitesse de combustion laminaire à partir de flammes en expansion sphériques

Abstract : Environmental and social challenges concerning the combustion of fossil fuels for energy production (electricity, building and transport) require the development of new combustion processes, new burner technologies and alternative fuels (gasification of biomass, biofuels, ...). Laminar burning velocity is one of the fundamental parameters used to characterize premixed combustion for these new fuels. This speed is a reference for the validation and improvement of kinetic schemes and an input parameter to estimate the turbulent burning velocity of most turbulent combustion codes. But even if it has been studied over 100 years, the precise experimental measurement of this velocity is still complicated due to inherent limitations in experimental configurations used, especially for high pressure and temperature conditions. In this context, this thesis work focuses on the study, analysis and characterization of the different techniques used to determine the laminar burning velocity from spherically expanding flames and proposes a reflection on the minimization of all possible uncertainty sources. This approach is achieved with confined spherical flames which allow to obtain high temperature and pressure initial conditions. In the first part, the formalism of existing laminar flame speeds in spherical expanding configuration is reminded to define the factors of uncertainty related to the experimental measurement (local kinematic and global kinetic variables). In particular, the effects associated with the estimation of the burned gases thermodynamic state, radiation and differential diffusion are discussed. In the second part, several numerical and experimental devices used in this thesis are presented. A study on four different experimental setups is proposed to analyze and characterize the uncertainties in the measurements and processing. Finally, in the third part, a rigorous definition of the consumption speed is proposed and a new methodology to measure it is developed. A complete validation based on numerical results is presented. Then uncertainties related to radiation, differential diffusion and extrapolation to zero stretch rate of measured data are detailed. This last step introduces a non-negligible bias and a new methodology to exploit raw data by a direct comparison with DNS reproducing the experiments is proposed.
Document type :
Theses
Complete list of metadatas

Cited literature [140 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-01429840
Contributor : Abes Star <>
Submitted on : Monday, January 9, 2017 - 11:15:05 AM
Last modification on : Thursday, November 28, 2019 - 3:50:39 AM
Long-term archiving on : Monday, April 10, 2017 - 1:45:26 PM

File

LEFEBVRE_-_Alexandre.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-01429840, version 1

Citation

Alexandre Lefebvre. Analyses théorique, numérique et expérimentale de la détermination de la vitesse de combustion laminaire à partir de flammes en expansion sphériques. Physique [physics]. INSA de Rouen, 2016. Français. ⟨NNT : 2016ISAM0009⟩. ⟨tel-01429840⟩

Share

Metrics

Record views

653

Files downloads

802