Upload
nguyenminh
View
217
Download
1
Embed Size (px)
Citation preview
ExperimentalcombustionresearchUK
Imperial
EdinburghStrathclydeGlasgow
SheffieldLeeds
Loughborough
Cardiff UCL
Brighton
Oxford
Cambridge
DDaannPPuugghh
ConstantVolumeBombHPOC/SwirlBurner
EPSRC- AGTCounterflowBurner
26th [email protected]
GGTTRRCCEEXXPPEERRIIMMEENNTTAALLCCOOMMBBUUSSTTIIOONN
SSttuuddyyLLaammiinnaarrFFllaammeePPrrooppaaggaattiioonn
- Schlierenopticaltechniqueemployedtomeasurelaminarflamespeed.
- Facilitatesparametricevaluationoftemperature,pressure,reactantmixtureandhumidity.
- CharacteriseflamestretchandinfluenceonpropagationusingMarksteinlength.
- Massflowcontroltoregulategaseousorvaporisedfuelandequivalenceratio.
Constantvolumebomb
WWoorrkkAArreeaass
- NaturalGas/CH4.
- Alternativefuels– syngases,biogas,industrialby-productgases.
- Parametricchangesintemperatureandpressure,derivingpowerlawcorrelations.
- Reactionmechanismoptimisation,anddevelopment.
- Contemporaryworkinvestigatingcatalyticenhancementofheavilycarbonaceousfuelswithwateraddition.
UUppccoommiinnggWWoorrkk
- Influenceofhigherhydrocarbonadditiontonaturalgas(LNG),andchangeinthermo-diffusiveinfluence.
- CorrelatingresultsagainstbehaviourwitnessedingenericGTrepresentativeswirlburner.
D G. Pugh, A P. Crayford, P J. Bowen, M Al-Naama, Parametric investigation of water loading on heavily carbonaceous syngases, Comb. & Flame, Vol 164, 2016, Pages 126-136,
http://dx.doi.org/10.1016/j.combustflame.2015.11.009
Constantvolumebomb
EExxppeerriimmeennttaallFFaacciilliittyyMMooddiiffiiccaattiioonn
- Injectandvaporiseliquidfuel,thenchargeairandover-pressurisethesystem.
- Rapiddecompressionfrominternalpistonformsquasi-homogenousmist,dropletscharacterisedwithlaserdiffractionsystem.
- Quantifytheinfluenceofobstacleinducedturbulence,withmixtureignitedfromtop.
- Opticaltachometersprovidescalablerotationalspeedtoinduceturbulenceintothesystem.
motor
ReflectiveSpot
Shaft
Fan
Tachometer
DDyynnaammiiccVVoolluummeeBBoommbb
SWIRLBURNER
HPOC
Plenum HPOCLance MixChamber AccessWindow
QuartzTubeNozzle
HHPPOOCC–– SSwwiirrllBBuurrnneerr
SSyysstteemmCCaappaabbiilliittyy
- Casingratedto900K,16bar.
- Axialandtangentialopticalaccess.
- Liquidorgaseousfuelsupply,withcombustorsoperatedinpremixedordiffusionconfigurations.
- Fivelinesallowforfuel/oxidantmixtureblending,withprecisemassflowcontrol.
- Convergentquartztubesfacilitateopticalaccess,withrepresentativecombustorgeometry.
- Pressurisedsteamsupplytofacilitatehumidifiedcombustion.
AAnnaallyyttiiccaallDDiiaaggnnoossttiiccTToooollss
- Opticaltechniquesincluding;highspeedfilming,Schlieren,Chemiluminescence,ParticleImageVelocimetry(PIV)andPlanarLaserInducedFluorescence(PLIF).Highfrequencypressuretransducersgiveacousticoutputofthesystem.
- Onlinegasanalysisforrealtimemeasurementofexhaustemissions,including;CO,CO2,NO,NO2,(TotalNOx),O2 andunburnedhydrocarbons.
HHPPOOCC–– SSwwiirrllBBuurrnneerr
CCoonntteemmppoorraarryyWWoorrkk
- FuelFlexibility- Investigatingchangesinnaturalgascomposition,(Gas-to-Power,LNG,H2,CxHy)forchangesinflameshape,burneroperability,emissions,andthermoacousticresponseofthesystem.
- CarbonFree‘Green’combustion- StabilisingblendedH2andNH3 forGTcombustorsandenergystorageapplications.
- ExhaustGasRecirculation- InvestigatechangeinCO2reactantfractionsonflameoperabilityandproducedemissions,andhowthismayinfluencedownstreamCCStechnology.
- Humidifiedcombustion- ReducingflametemperatureswithH2OtoreduceNOx emissions.WorkpresentedatASMETurboexpo2017.
OH*Chemiluminescence AbelDeconvoluted
OHPLIF
NOx Emissions
D.G. Pugh, P.J. Bowen, R. Marsh, A.P. Crayford, J. Runyon, S. Morris, A. Valera-Medina, A. Giles, Dissociative influence of H2O vapour/spray on lean blowoff and NOx reduction for heavily carbonaceous syngas swirling flames, Comb. and Flame, Vol. 177 Pages 37-48
2017http://dx.doi.org/10.1016/j.combustflame.2016.11.010.
HHuummiiddiiffiieeddCCOOWWoorrkk
0 50
75
0 0.006 0.012 0.024 0.046 0.088 0.145
Scaleinmm
10
0
ConverterGas/ Air/ H2O CH4 / Air200ImageAverage
MolarReactantH2OFraction0
Re- 17.8 Re- 17.9 Re- 18.1 Re- 18.3 Re- 18.7 Re- 19.5 Re- 20.8 Re– 18.5
0.4
0.42
0.44
0.46
0.48
0.5
0.52
0.54
-0.02 0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16
LBO
Equ
ival
ence
Rat
io(Ø
)
MolarReactantH2OFraction
T– 423K
CO(D
ry1
5%O
2)–
ppm
V0
10
20
30
40
50
60
-0.02 0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.160
20
40
60
80
100
120
140
160
-0.02 0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16
MolarReactantH2OFraction
NO
x(D
ry1
5%O
2)–
ppm
V
MolarReactantH2OFraction
50-80%molCO
10-18%molCO2
10-15%molN2
1-3%molH2
CCoouunntteerrfflloowwBBuurrnneerr
EExxppeerriimmeennttaallFFaacciilliittyy
- Counterfloworopposedflowburnersstabiliseflamesbetweenconcentricjets.
- Allowingmeasurementoflaminarflamespeed,turbulence,extinctionstrainrate,chemicalspeciationandsootformation.
- Reactantsshroudedwithinertflowtopreventsecondaryflameformation.Setupcanbeconfiguredforpremixedordiffusionflames.
CCoouunntteerrfflloowwBBuurrnneerr
DDeevveellooppmmeennttoofftthheeCCaarrddiiffffFFaacciilliittyy
- Imperialdesignmodifiedtooperateatelevatedtemperature(473K)andpressure(10bar).
- Reactantpreheatwillfacilitatecombustionofprevaporisedliquidfuels,andhumidifiedcombustion.
- Diametricquartzwindowswillallowfortheapplicationofopticaldiagnostictechniques.
- DesignhasallowedfortrialofcomponentsbuiltusingAMor‘3Dprinted’stainlesssteeltechnology,withintegratedcoolingchannels.
- Planstotestappliedequivalenceratiomeasurementtechnique,employingquantifiedchemiluminescenceratios.
Turbulentflows• Scalar / Thermal Dissipation rate conditional on mixture fraction in
swirling flows with and without reaction • Development of scalar dissipation rate measurements for non-reacting and
reacting flows - Experiments in Fluids 55, (2014) • Measurements of Scalar Dissipation rate in unsteady gas jets, simulating
automotive injectors – Physics of Fluids 27, (2015)• Measurements of scalar dissipation rate in non-reacting Swirl burners.
Experimental evaluation of SGS models for LES and quantification of the behaviour in the flows – Physics of Fluids 27, (2015), and Physics of Fluids 28, (2016)
• Development of thermal dissipation rate measurements in swirl-stabilisedburners based on Rayleigh Scattering – publication in preparation
• Measurements of Velocity, Temperature, Thermal dissipation rate in swirl stabilised burner using PIV and Rayleigh – publication in preparation
• Flow-Flame interactions• Simultaneous multiple plane measurements of reaction zone and flow
velocity field [with emphasis on fractal grid flames]. [Fluid Dyn. Res. 45, (2013); Proc. Comb Inst. 35, (2015) & Combustion and Flame 162, (2015); publication in preparation]
• Volumetric measurements in swirl stabilised burner - starting Jan. 2018. This will include flow velocity, reaction zone and fuel concentration
• Laser Ignition of jets of gas and liquid fuel• Experiments in Homogeneous Isotropic Turbulence without mean flow at various levels of
turbulence [Proc. Comb Inst. 36, (2017); ongoing]
• Development and application of Laser Diagnostics• Development of LIBS for Air-Fuel ratio measurements in flames. Sensors for monitoring
fuel variability. Applications in swirl burners and gas turbine combustors [18th Int Sympon Applications of Laser Techniques to Fluid Mechanics, Lisbon, Portugal, 4-7 July 2016; ECM 2017; ongoing]
• Flame Chemiluminescence for different fuel blends. Experiments and Detailed chemistry calculations. Sensors for flame monitoring of heat release rate and air-fuel ratio. Application in swirl burners and gas turbine combustors. [AIAA paper 2017-0153; ECM 2017; ongoing]
• CO Laser Induced Fluorescence in Reacting flows – [ongoing]• Development of plenoptic imaging (camera and processing software) [21st ILASS-Japan,
Tokyo, Japan, 17-18 December 2012; 18th Int Symp on Applications of Laser Techniques to Fluid Mechanics”, Lisbon, Portugal, 4-7 July 2016; ongoing]
• Development of novel flow velocimetry and temperature technique that operates without seeding particles [patent pending]
Gasturbinecombustion• Combustion oscillations and control of emissions
• Development of tools for prediction of self-induced combustion oscillations and associated control [ECM 2017; ongoing]
• Non-linear dynamics of time-dependent pressure, flow velocity and heat release rate with and without oscillations [publication in preparation; ongoing]
• Time dependent PIV velocity measurements and OH PLIF measurements conditional on pressure under combustion oscillations [partly complete-preparation of publications; ongoing]
• Effects of Fuel variability and fuel or air dilution by inert gases on combustion [ongoing]
Burnerstudies
• Laminarflames(SantoroandGülder,left)• Firewhirl /firetornado(centre)• Turbulentnon-premixedburner– oxy-fuel(right)
Opticaldiagnostics
• Temperature(LITGS,Rayleigh,pyrometry)• Sootvolumefraction(pyrometry,extinction)• Particlesize(staticlightscattering)• Tomography• RadicalspeciesbyLIFandchemiluminescence
• OH,CH,CH2O,CN…• Localisedextinction;heatreleaseimaging• ParticleImageVelocimetry,~10Hzand8kHz
• Newlaserdiagnosticslabsinbuildnow
Othermethods/comments
• Non-opticalmethods:• Thermophoreticsamplingwithelectronmicroscopy• Finegaugethermocouplescan• Hotwireanemometry
• Exhaustsampling:• Cambustion Fast-FID• Cambustion DMS500
• Laminarburnersarequiteportable
OxfordColdDrivenShockTube
• Transienttestfacilitythatcanreproducee.g.dieselcombustionconditions
• Optically-accessibletestsection• Construction/commissioninginprogress
CLOSEUPOF70X30MMOPTICALACCESSWINDOW(x3)
• CENTRALLYMOUNTEDSINGLEHOLEDIESELINJECTOR–ECN‘SPRAYA’
• HEATEDFUEL,1700BARINJECTIONPRESSURE
CDSTcapabilities/diagnostics
• Opticaldiagnosticsactivity• Highspeedspraycombustionimaging:shadowgraphy,schlieren,
Miescattering.LITGS
• Ignitiondelay• Opticaltechniquesorcapturepressureriseatsidewall
• Pre-mixedchemicalkineticsstudiesalsoplanned,withorwithoutspraycombustion(dualfuelling)
Condition Pressure(bar)
Temperature(K)
Testduration(airdriven,ms)
Testduration(Hedriven,ms)
LowCondition 50 500 5 14
Design– ECN‘SprayA’
60 900 3 10
Highcondition 120 1500 - 8
Measurement techniques:• Flame studies based on laser-induced fluorescence (LII) and laser-induced incandescence (LIF):
• Polycyclic aromatic hydrocarbons (PAH)• Nanoparticulates / soot• Intermediates: OH, CH• Temperature
• Cavity-ring down and cavity-enhanced absorption spectroscopy:
• Sensitive concentration measurementsIntermediates: OH, 1CH2, HCO, C2H2
University of StrathclydeDr Iain Burns
Diode laser cavity ring-down spectroscopy in flames
• Previous cavity ring-down work in flames had been based on pulsed dye lasers• Near infrared diode lasers are used here for in situ cw-CRDS• Applied to measure acetylene concentration profiles in rich ethylene-air flames
Humphries,G.S.etal.(2016).IEEEPhot.J.,8(1),3900110
LII using a Long-Pulsed Fibre Laser• For reasons of practicality and safety it may be
attractive to use pulsed fibre lasers when performing LII in industrial test environments
• Their optical properties differ from typical Nd:YAG lasers, including much longer pulse length
• LII with long-pulse fibre lasers has been compared to reference measurements by ‘standard LII’ in a stable flat-flame
RobertRoyhasaposter
Mastorakos• EXPERIMENTAL
• Swirlflames:extinction,ignition,flametransferfunctions
• Annularcombustor:flametransferfunctions,light-round
• Diagnostics:10kHzOH-PLIF,10HzOH-PLIF,10HzCH2O-PLIF,LIBS
• COMPUTATIONAL
• LESwithConditionalMomentClosure:ignition,blow-off,emissions
Spraycombustion
experiments
Chong, C.T., S. Hochgreb, Spray flame structure of rapeseed biodiesel and Jet-A1 fuel, Fuel. 115 (2014) 551–558 doi:10.1016/j.fuel.2013.07.059.
MohdYasin, M. F ., Cant, R.S., Chong, C.T., Hochgreb, S. Discrete multicomponent model for biodiesel spray combustion simulation, Fuel. 126 (2014) 44–54 doi:10.1016/j.fuel.2014.02.020.
diesel
PME
OH*model
droplet flux
ThermographicPIV
Fan,L.,Gao,Y.,Hayakawa,A.,Hochgreb,S.,2017.Exp.Fluids58,34.DOI:10.1007/s00348-017-2313-2
• Extensions:higherT• Heattransfer• LDA(Heyes/Strathclyde)
HighresolutionsootvolumefractionviacavityextinctionandLII
Tian,B.,Gao,Y.,Balusamy,S.,Hochgreb,S.,2015.Appl.Phys.B120,469–487.DOI:10.1007/s00340-015-6156-3
- extension:liquidfuels- carbonnanotubes- nano oxides
Laser-InducedThermalGratingSpectroscopy(LITGS)
Pump
Pump
Thermal Grating
ProbeLITGS signal
𝜏𝜏 =Λ𝑐𝑐𝑠𝑠
[N2]/([N
2]+[O
2])
0.5 0.55 0.6 0.65 0.7 0.75 0.8 0.85
Te
mp
era
ture
(K
)
1600
1800
2000
2200
2400
2600
2800
3000
3200
LITGS temperature
Adiabatic flame temperature
OH/5barCH4flame
measurec
Extension:• 1kHzc measurementsentropyspots@355nm
(thermoacoustics)
Hayakawa,A.,etal.,2016.JapaneseSymposiumonCombustion,November23-25,Sendai,Japan.p.P102.
Directnoise
Indirectnoise
DeDomenico/Fan/Williams/Shah/Hochgreb
CERS– CavityenhancedRamanspectroscopy
36
F𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖 =𝐹𝐹𝐹𝐹𝐹𝐹
𝐹𝐹𝐹𝐹𝐹𝐹𝐹𝐹
Finesse=1000
C-H
𝐹𝐹� = 99.9935% 𝐹𝐹� = 99.997%
𝜆𝜆�
𝜆𝜆�𝜆𝜆�
𝜆𝜆� = 532mm
Furtherafield
Sheffield(Pourkashanian):- Downwardfiredcoal- CCS- Kineticsofalternativefuels
Leeds(Lawes,Bradley):- Combustionbomb- Turbulentcombustion- Blowoff/liftoff
Edinburgh(Linne,Peterson):- Femtoseconddiagnostics- Sprays- Walleffectsinengines
UCL:- Heatreleaseimaging
Loughborough(Carrotte):- Highpressurecombustion
facility
SummaryCAM CARD IMP OXF STR OTHER
Comb.Bomb
x x
Lamflame
x x x x x
Shocktube
x
Turb.FlameImaging
x x x EDINUCL
Sprays x x x x EDINBRI
Highpressure
x x EDIN
Diag.develop.
x x x
Futureopportunities• Joiningexistingfacilitiesanddiagnosticscapabilitiesfor
addressingdifficultproblems(e.g.shocktube+cw laserdiagnostics;highpressurefacilities+imagingdiagnostics,highfrequencydiagnostics+entropyspots)
• Exchangingexperience:trainingPhD/RAsinawiderrangeoftechniques(e.g.TDLAS,PIV)oringreaterdepth
• Addressingkeyproblemsinmodelling(e.g.subgridassumptions,assumedclosurepdfs),andmotivate/justifynewfacilities/projects(e.g.fs-CARSatEdinburghfordetailedworkinflames)
• … andmuchmuchmore…