Two dimensional Laser Induced Plasma Spectroscopy for the measurements of local composition in gaseous flow and sprays - Archive ouverte HAL Accéder directement au contenu
Communication Dans Un Congrès Année : 2012

Two dimensional Laser Induced Plasma Spectroscopy for the measurements of local composition in gaseous flow and sprays

Résumé

An extension of the Laser Induced Plasma Spectroscopy technique has been presented to achieve a very high spatial resolution. It is based on the simultaneous recording of the plasma with cameras equipped with different interferential filter centered on the main atomic emission wavelengths. For mixing between air and nitrogen, emissions of N(744) and O(777) are used whereas for ignition tests, H(656) is chosen for the fuel and O(777) for the oxidizer. Exact calibration procedure is explained and typical results obtained in a laminar burner using air and nitrogen are presented. This technique can be easily coupled to other planar images, like Particle Image Velocimetry to yield simultaneous velocity and scalar information. Typical uncertainties were quantified in a laminar burner and are lower than classic (0D) LIPS approaches. A procedure to obtain spatially resolved energy deposition has been proposed based both on the mixture fraction measurement and the absolute intensity of oxygen emission. It is shown that oxygen emission is influenced by both energy and mixture fraction. Using simultaneous measurements with two cameras, the effects of mixture fraction can be estimated and an evaluation of the energy deposited can be done. An application in a combustor using liquid fuel has been shown and the spatial resolution of the technique could determine the influence of the droplets as creating multiple sparks. Furthermore, using the ratio between hydrogen and oxygen, it was shown that typical ignited sparks were those with high concentration of hydrogen localized in space. Using the approach proposed in the paper to estimate local energy, those regions were also regions in which the major part of the energy was deposited. Finally, it is possible to combine the data obtain by this new technique with time resolved PIV data to fully understand the dynamics of laser ignition in liquid fuelled combustor.
Fichier non déposé

Dates et versions

hal-00779442 , version 1 (22-01-2013)

Identifiants

  • HAL Id : hal-00779442 , version 1

Citer

Tapish Agarwal, Laurent Zimmer. Two dimensional Laser Induced Plasma Spectroscopy for the measurements of local composition in gaseous flow and sprays. 16th Int Symp on Applications of Laser Techniques to Fluid Mechanics, Jul 2012, lisbonne, Portugal. pp.321. ⟨hal-00779442⟩
114 Consultations
0 Téléchargements

Partager

Gmail Facebook X LinkedIn More