Skip to Main content Skip to Navigation
Theses

Etude du mélange et de la combustion dans les flammes jets subsoniques à haute vitesse : influence des vitesses, des densités et de la composition du combustible

Abstract : This study deals with combustion optimization of subsonic jet flames in the combustion chambers of air breathing propulsion systems. The effects of velocity ratio r = Uair/Ufuel, density ratio s = ρair/ρfuel and mixture composition (H2 and CH4/H2 mixture) on mixing and combustion are characterized experimentally. We evidence that mixing is not affected by the density ratio, whereas it increases with decreasing velocity ratio. The mixture composition does not affect the mixing either. Therefore results display a mixing drive by the aerodynamic mixing: the molecular diffusion is unimportant compared to the turbulent diffusion. The combustion study shows that the velocity ratio and the density ratio do not affect the fuel consumption rate; whereas it decreases with the increasing methane introduction in the mixture CH4/H2. Due to the slower chemical kinetics of CH4/ air combustion, local flame extinctions arise. The study of heat release in the H2/air flame shows an increase with decreasing velocity ratio. Finally, we put forward a conditioned combustion length due to the containment, owing to the external flow acceleration.
Document type :
Theses
Complete list of metadatas

Cited literature [23 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-00443950
Contributor : Bénédicte Carouge <>
Submitted on : Thursday, January 7, 2010 - 11:26:11 AM
Last modification on : Thursday, March 7, 2019 - 3:08:06 PM
Long-term archiving on: : Friday, June 18, 2010 - 12:20:10 AM

Identifiers

  • HAL Id : tel-00443950, version 1

Collections

Citation

John Grondin. Etude du mélange et de la combustion dans les flammes jets subsoniques à haute vitesse : influence des vitesses, des densités et de la composition du combustible. Sciences de l'ingénieur [physics]. ISAE-ENSMA Ecole Nationale Supérieure de Mécanique et d'Aérotechique - Poitiers, 2009. Français. ⟨tel-00443950⟩

Share

Metrics

Record views

569

Files downloads

8634