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T.KoトISHIandA.lTo
20
18 7
Eコr-ー「
(b) Time(sec) 一。-0.2
一口ー 0.4 。一-0.6 一会一1.0 ー 乎 -2.0
5 10 15 20 Concentration[vol%]
~~6 15 g:5
喜s
10
5 ーロ
→「 ω 2 δ t~
Z~
O
~t告
3
4
Fig.4.Atypicalinterferograrnpicture(a)andtransientconcentrationprofiles(b).
surfaceternperaturebyaninfraredcarneraisalso conductedforrnethanolasshowninFig.5(b).Atthe 30 rnornentwhentheshuterisopened，theCrGLrapidly decreasesduetothesurfaceternperaturedropby evaporation.Subsequentlythesurfaceconcentration gradualyincreasesduetothesurfaceternperature increasecausedby liquidconvectionunderneaththe
fu.elsurface.
Thesurfaceternperaturedropandtheconsequent CrGLdescentaredeterninedbythecornbinationofone dimensionalunsteadydifusionequationand1-D unsteadyheatconductionequation.Theconcentration profilesoverfuelsurfacecanbecalculatedbythe folowingl-Ddifusionequation.
(1)
dt ¥dZ2J wherecAisconcentrationofspeciesAandDABis 5
(a)
Fue!temp巴rature[・c]
dCA ，.，. fd2CA¥ ー一 一 一= =-UABI一 一 一 一 l
themutual-difusioncoeficientofspeciesA ingasB. ThesubscriptsA andBdenotefuelvaporandair， respectively.Thisequationistobesolvedwiththeinitial 30 andboundaryconditions:
r.c.: at t=O，
B.C.1:at z=o， CA=CAO B.C2:at z=∞ cA=O
HereCAOistheequilibriumgas-phaseconcentration. Equation(1)canbeintegratedeasilytogivethe fol1owingconcentrationprofiles:
CA(Z，t)=吋 1-erf-;:=.乙一| (2) Y4DAIltJ
Oncetheconcentrationprofileshavebeendeternined，
themassfluxJ offuelvapor仕ornasurfaceareaScan
z~{l
becakulated.Ift.heheatofevaporationisexpresed byilHvap，theheatfluxatthegas-liquidinterfaceis
24
Fig.5.HistoriesofCrGLfordiferentsurface temperature(a)andthechangeofthesurface temperaturemeasuredbyinfraredcamera(b).
cA=0 28 26
25
20
32
lnitialfuel temperature
31.00 C 29.YC
24.50 C
22O 1 2 3
Time[s]
ハu nU
+ 4 + 士主 4
口 〈 VAU マ 包 団
二三十十
世 ωJrFH
XMM ん凸早官官 口FOA マ図田
〉口仁OKAV絹 、戸JAU
[s-okr]JOHU
むし 255ω仏E386°Cロ∞
il: fiihli-1-1111 111;l-il l iJIlil i --1 1
