1. HanShen
PORTFOLIO
MechanicalandAerospaceEngineering

2. CONTENTS
Acomplexburnerusedtounderstandtheeffectsof
chemicalreactionandheatreleaseonturbulentcom-
bustionenergycascade
Aserialofexperimentsdesignedtounderstandthe
fundamentalsofdimethylethercombustionanditsdif-
ferencesfromwell-establishedmethanecombustion
Aninnovativedesignofaturbofanenginewithbypass
ratioof12,integratingwithfloatinggearbox,hybrid
thrustreverseranddouble-domecombustor
Alight-weighttwo-seatelectricairplanewithpushercon-
figuration;Designandanalysisofaerodynamicsand
structuresaswellascontrolsystem
Acomplexgassupplysystemforvariableoxidizersand
fuelswithcompatibleautomateddigitalcontrol
Designandbuildofaremotecontrolbi-planewithcom-
binedweightof50pounds,endingin10thplaceinthe
2011SAEAeroDesignCompetition

3. Turbulentcombustionisthekeyphenom-
enoninthemajorityofpropulsionsystems;
however,thebasicphysicsremainpoorly
understood,especiallyunderhigh-Reynolds
numberconditions.Turbulentcombustion
processesaretime-varying,spatiallycom-
plex,andaregovernedbymulti-physicsand
multi-scalephenomena.Theseaspects
creategreatdifficultiesfordevelopingade-
tailedunderstandingofbasicphysicaland
chemicalprocessesthatunderpinturbulent
combustionenvironmentsaswellasprovid-
ingpredictiveandphysically-basedmodels
thataccuratelydescribetheirbehavior.
Premixedcombustionisacombustion
modewherethefuelandoxidizerarecom-
pletelypremixedpriortotheflamereaction
zone;thismodeofcombustionhasbeen
showntobeapromisingmethodtomaxi-
mizecombustionefficiencyandminimize
pollutantformation.Thecontinuedandfur
therapplicationofpremixedcombustionto
practicalapplicationsislimitedbythecur-
rentunderstandingofturbulentpremixed
combustion;theselimitationsinunderstand-
ingarelinkedtothespecificflamephenom-
enathatcansignificantlyinfluencepre-
mixedcombustioninacombustiondevice,
suchasrocket.



4. Thisexperimentoutlinesanefforttoinvestigatethe
multi-scaleandmulti-physicsnatureofinstantaneous
andnetenergytransferinhighlyturbulentflameswith
carefulconsiderationgiventotheresultsinthecontext
oflarge-eddysimulation(LES).Specificemphasisis
placedon(i)understandingtheeffectsofchemicalre-
actionandheatreleaseonturbulentenergycascade,
(ii)differencesinkineticenergyandscalarvariance(ii)differencesinkineticenergyandscalarvariance
(“scalarenergy”)transfer,and(iii)thephysicalmecha-
nisms(i.e.,dynamicsandnon-linearinteractions)that
leadtolocalreverseenergytransferfromsmallscales
tolargescales(i.e.,“backscatter”),whichmaybecome
exceedinglyimportantunderhigh-Reynoldsnumber
reactingflowconditions(andwhenconsideringLES).
Toachievethegoal,anexperimentalburnergeom-
etryhasbeendeveloped:thePilotedPremixedJet
Burner(PPJB).ThePPJBfeaturesasmall4mmdi-
ametercentraljetfromwhichahighvelocity
lean-premixedmethane-airmixtureissues.Sur-
roundingthecentraljetinthePPJBisa23.5mmdi-
ameterpilotofstoichiometricmethane-airproducts.
ThepilotinthePPJBprovidesarichsourceofcom-
bustionintermediatesandenthalpywhichpromotes
initialignitionofthecentraljetmixture.Surrounding
thecentraljetandpilotisalargediameterhotcoflow
ofcombustionproducts(hydrogen).Thepremixed
centraljetandpilotreactantsflowthroughthePPJB
bodyinsideconcentricstainlesssteeltubes.

6. Thefirstweekoftheburneroperationwastestrunfor
developingoperationprotocol.Alotofproblemsweredis-
coveredduringthefirstweek,buttheywereallworkedout
afterre-calculatingandmodifying.Adetailedoperation
protocolwaswrittenforfuturestudents’usage.
Severaldifferentcombustiondiagnosticstechniques
wereperformedincludingformaldehydePLIF,OHradical
PLIF,particleimagevelocimetry,Rayleighscattering,and
highspeedlaserdiagnostics.Thesetechniqueswere
usedtobuildafundamentalunderstandingofenergy
transferinahighlyturbulentreactingflow.

7. Themainpurposeofthisprojectistostudytheenergytransferinreactingturbulentflow.Onaverage,
energytransfersfromlargescalestosmallscales(”forwardscatter”);energytransferfromsmallscalesto
largescalesiscalled“backscatter”.Thedetailsofenergytransferhasbeengivensolittleattentioninreact-
ingflowsthatmajorityofstudieshavebeeninnon-reactingflow.Thepreliminaryresultsshowthatnegative
sub-gridscaledissipationvaluesareassociatedwithlargevaluesofnegativevorticity,whichprovesthat
backscatterisobservedexperimentallyandappearstobeofimportance.
FromthetemperatureandformaldehydePLIFresults,itshowsthatthermalgradientlayersdecreasein
thicknesswithincreasingvelocity.Furthermore,thenearexitregimeresemblesmixingprobleminsteadof
combustion.

13. Themajordesignpointsthatmustbemetby
theengineinnetuninstalledthrustsare:
•TakeoffThrust,FTO =19,000lbfatsealevel/
0.25Mach/ISA+27F
•Top-of-ClimbThrust,FTopofClimb=6000lbfat
35,000ft/0.80Mach/ISA
••BucketCruiseThrust,Fbucket=4500–5000lbf
at35,000ft/0.80Mach/ISA

14. GraphiteFiber
Composite
Titanium
Theturbomachineryofenginecoreissplitintotwospools:onespool
connectsthehigh-pressureturbineandcompressor,whiletheother
shaftconnectsthelow-pressureturbine,compressor,andgearbox.
Componentscoexistingonthesamespoolsharethesamerotational
speed,howeverthein-linegearboxallowsthefanandlow-pressure
spooltooperateatdifferentspeeds.
Therotorbladesofthefanstagearetobe
manufacturedwithagraphitefiberandepoxy
compositefollowingtheresearchperformedat
theNASAGlennResearchCenter.Usingcom-
positematerialreducestheweightofthefan
bladesbyalmosttwo-thirdsascomparedtothe
standardtitanium.
Topassivelyabsorbsoundenergy,Helmholtzresonators
thatcomprisetheacousticlineraretailoredtooscillatewith
anaturalfrequencythatmirrorsthedominantbladepassing
frequencyofthefanblade.
Adouble-annularcombustoris
chosentobedesignedtomeetthere-
quirementsofloweremissionsanda
smallsize.