Laser Diagnostics Applied to Lean Premixed Swirling Flames - Simultaneous Flow Field and Scalar Measurements
type: CreativeWork
description: The work reported here includes experimental studies of lean premixed swirling flames. Various laser-based optical diagnostic techniques were used to collect information under different operational conditions. Combined flow- and scalar field measurements were performed at high repetition rates for detailed studies of the turbulent flames. A large part of the work presented concerns experimental studies of lean turbulent premixed flames stabilized by a low-swirl burner. The unconfined flames that were studied were propagating in a divergent flow field and interacted with flow structures in the shear layers surrounding them. Particle Image Velocimetry (PIV) and stereo-PIV were employed for velocity measurements in a given plane. Volumetric Velocimetry (3D PIV) was performed in order to assess the full 3D characteristics of the flow field. Flame-front visualization and fuel distribution measurements were obtained by use of Planar Laser Induced Fluorescence (PLIF). PLIF of OH radicals, created in regions where high temperature reactions occurred, were used to determine the position, fluctuation, overall shape and wrinkling of the flame front. Simultaneous measurements, performed at repetition rates of several thousand images per second, of the velocity field and of flame location enabled information concerning the flow strucutres emanating from the nozzle and the flame flow interaction. The results obtained were used for validation of Large Eddy Simulations (LES), carried out by collaborating groups in parallel with the experiments. The influence of the inflow boundary conditions were investigated using both experimental data and LES of the flow through the swirler and nozzle. An investigation of flames close to flashback was carried out in a burner having a variable degree of swirl and equipped with an transparent nozzle. PIV and high-speed video of the flame luminosity were used to study the transition to flashback when the degree of swirl was increased. The observed …
abstract: The work reported here includes experimental studies of lean premixed swirling flames. Various laser-based optical diagnostic techniques were used to collect information under different operational conditions. Combined flow- and scalar field measurements were performed at high repetition rates for detailed studies of the turbulent flames. A large part of the work presented concerns experimental studies of lean turbulent premixed flames stabilized by a low-swirl burner. The unconfined flames that were studied were propagating in a divergent flow field and interacted with flow structures in the shear layers surrounding them. Particle Image Velocimetry (PIV) and stereo-PIV were employed for velocity measurements in a given plane. Volumetric Velocimetry (3D PIV) was performed in order to assess the full 3D characteristics of the flow field. Flame-front visualization and fuel distribution measurements were obtained by use of Planar Laser Induced Fluorescence (PLIF). PLIF of OH radicals, created in regions where high temperature reactions occurred, were used to determine the position, fluctuation, overall shape and wrinkling of the flame front. Simultaneous measurements, performed at repetition rates of several thousand images per second, of the velocity field and of flame location enabled information concerning the flow strucutres emanating from the nozzle and the flame flow interaction. The results obtained were used for validation of Large Eddy Simulations (LES), carried out by collaborating groups in parallel with the experiments. The influence of the inflow boundary conditions were investigated using both experimental data and LES of the flow through the swirler and nozzle. An investigation of flames close to flashback was carried out in a burner having a variable degree of swirl and equipped with an transparent nozzle. PIV and high-speed video of the flame luminosity were used to study the transition to flashback when the degree of swirl was increased. The observed …
author: Petersson, Per
language: eng
keywords: Atom and Molecular Physics and Optics, Volumetric Velocimetry, Low-swirl Flames, Premixed Flames, Turbulent Combustion, Particle Image Velocimetry, Laser Diagnostics, A.2014:Petersson, Combustion Diagnostics
date published: 2014
date modified: 2026-07-24T02:59:36Z
provider: University of Lund
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Division of Combustion Physics, Department of Physics, Lund University