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19970012645.Pdf | Trade names or manufacturers' names are used in this report for identification only. This usage does not constitute an official endorsement, either expressed or implied, by the National Aeronautics and Space Administration. TABLE OF CONTENTS Page LIST OF TABLES .................................................................................................. vii LIST OF FIGURES ..................... ............................................................................ xiii .oo LIST OF SYMBOLS .............................................................................................. xvm ABSTRACT ............................................................................................................ xxv CHAPTER 1 • INTRODUCTION ........................................................................ 1 1.1 Background .............................................................................................. 1 1.2 Content of Dissertation ............................................................................. 2 CHAPTER 2 • CHEMILUMINESCENT MEASUREMENTS OF NITRIC OXIDE FORMATION BY INVERSE DIFFUSION FLAMES IN STAGED-AIR BURNERS ....................................................... 5 2.1 Introduction .............................................................................................. 5 2.2 Experimental Apparatus ............................................................................ 6 2.3 Sampling/Analyzer System ........................................................................ 8 2.4 Experimental Procedure ............................................................................ 10 2.5 Results ........................................... ........................................................... 14 2.6 Discussion ................................................................................................. 19 2.7 Conclusions on Chemiluminescent Measurements ...................................... 23 CHAPTER 3 • PREVIOUS PLIF MEASUREMENTS ......................................... 24 3.1 Overview of the PLIF Technique ............................................................... 24 3.1.1 General PLIF Experimental Configuration .......... : .......................... 24 3.1.2 General ICCD Description ............................................................. 26 3.1.3 General PLIF Theory ..................................................................... 29 3.2 Review of Literature ................................................................................. 32 3.2.1 PLIF Temperature Measurement ................................................... 32 3.2.2 PLIF Velocity and Pressure Measurements .................................... 34 3.2.3 PLIF Species Measurements .......................................................... 36 3.3 State of PLIF Concentration Measurements .............................................. 39 Page CHAPTER4 : FLUORESCENCETHEORY : APPLICATIONSTO PLIF MEASUREMENTSOFNO..........................................................43 4.1 SpectralandTemporalProfile Considerations...........................................44 4.1.1 LaserPulseDescription.................................................................44 4.1.2 AbsorptionandEmissionLineshapeDescriptions..........................47 4.1.3 Formulationof the SpectralOverlapIntegral.................................48 4.2 Applicability of RateEquationAnalysis.....................................................51 4.3 Model of MolecularDynamics...................................................................53 4.3.1 RateEquationDescriptionof MolecularDynamics........................ 53 4.3.2 PhotonEmissionRatefor Fluorescence.........................................58 4.3.3 PhotonCollectionRatePerPixel...................................................59 4.3.4 Inclusionof SpectralandTemporalDependance............................61 4.3.5 Application of SpectralFilters........................................................62 4.3.6 Amplification andDigital ConversionbytheICCD........................63 4.3.7 FormulationUsingtheSaturationSpectralIrradiance.................... 65 4.4 Linear Fluorescence..................................................................................66 4.5 SaturatedFluorescence.............................................................................68 4.5.1 SaturatedFluorescenceTheory......................................................68 4.5.2 Influenceof LaserParameters........................................................71 4.5.3 SpatiallyExtendedSaturation........................................................72 CHAPTER5 : EXPERIMENTAL APPARATUS.................................................79 5.1 LaserSystem.............................................................................................79 5.1.1 LaserOperation.............................................................................79 5.1.2 PyrrometheneLaserDye Development..........................................82 5.2 ExcitationOptics.......................................................................................90 5.2.1 CommonExcitation Optics............................................................90 5.2.1.1 FresnelAttenuator...........................................................90 5.2.1.1 RochonPrism..................................................................92 5.2.2 LSFSpecificExcitation Optics......................................................94 5.2.3 PLIF SpecificExcitation Optics.....................................................94 5.3 Detectionsystems.....................................................................................97 5.3.1 CommonDetectionElements........................................................99 5.3.2 LSF SpecificDetectionElements...................................................100 5.3.2.1 CollectionOpticsi............................................................100 5.3.2.2 Monochromator..............................................................102 5.3.2.3 PMT Detector..................................................................104 5.3.3 PLIF SpecificDetectionElements..................................................106 5.3.3.1 PLIF EquipmentDescription...........................................106 5.3.3.2 ICCD AlignmentandSpecifications................................108 iii Page 5.4 OverlapReferenceSystem.............................................:........................... 114 5.5 DataAcquisition System...........................................................................116 5.6 Triggering System.....................................................................................117 5.6.1 LSF SpecificTriggering system.....................................................119 5.6.2 PLIF SpecificTriggering system....................................................121 5.7 AIDF Burner,Flow, andTranslation.........................................................124 CHAPTER 6 • EXPERIMENTAL ASSESSMENTOF02 INTERFERENCES ON LIF MEASUREMENTSOFNO IN HIGH-PRESSURE, LEAN PREMIXED FLAMES USINGNARROW-BAND AND BROAD-BAND DETECTION.....................................................129 6.1 Background..............................................................................................129 6.2 ExperimentalApparatus............................................................................132 6.3 Selectionof NO ExcitationLine................................................................136 6.4 Excitation Spectra.....................................................................................139 6.4.1 ExperimentsandResults................................................................139 6.4.2 SpectralIdentification....................................................................139 6.4.3 Observationsfor Narrow-BandDetection......................................144 6.4.4 Observationsfor Broad-BandDetection........................................144 6.5 EmissionSpectra.......................................................................................146 6.5.1 ExperimentsandResults................................................................146 6.5.2 SpectralIdentification....................................................................149 6.5.3 Observations.................................................................................151 6.6 Broad-BandSpectralFilter Evaluation......................................................153 6.6.1 Filter-AnalysisNomenclature.........................................................153 6.6.2 Filter AssessmentCriteria..............................................................156 6.6.3 Calculationof Filter AssessmentParameters..................................157 6.6.4 Filter AssessmentResults..............................................................161 6.7 Conclusionson02 Interferences................................................................169 CHAPTER7 " NITRIC OXIDE CONCENTRATIONMEASUREMENTS• PLIF ASSESSMENTAND ENHANCEMENT.............................171 7.1 LSF NO ConcentrationMeasurements......................................................173 7.2 PLIF NO ConcentrationMeasurements.....................................................174 7.3 PLIF ImageAssessment............................................................................178 7.4 Experimentally-BasedPLIF EnhancementProcedures...............................184 7.4.1 Single-InputPLIF EnhancementProcedure................................... 186 7.4.2 Multiple-Input PLIF EnhancementProcedure................................191
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