Page 115 - konishipaper

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Fig.5 FourdiferentLSPT-flowdiagramsobtainedforthepulsating f1amesteps(a，b，c，andd1)
resolutioncausedbyimageprocesingdiscretenes，ca1ibration erorofdistance，and血etimev紅 iationofthehigh-spedcamera. The precision and bias lirnits are listed in Table 1. The .total uncertain，句 ofLSPTisestimatedtobe:t8.6p町 cent.
originaldiagra皿 publishedin191(Ito，Masada，andSaito，191)， wasaddedbecauseithelpsusbeterunderstandtheprocesof fla皿 ep凶 sation.
Atstep(a)theflamespreadsslowlytotheleftandtheremaybe abuoyancy-inducedairflowoverthefuelsurfaceaheadof出e fi創ne.百lereisahotzoneformed担 theliquidphasenearthe fiame'sleadingedge，butnosurface-tensionflowisformedin吐le liquidphase.Atstep(b)也e宜amepropagatedfaster由 印 加 step(a) generatingasurface-tension(Margoaiefect)宜ow由at自ows白 血e samedirectionas也e宜ame.Inthegasphase，thereisabuoyancy- inducedairflowthatmovesopositeto出eflame-spreaddirection. '1泊'he加bu句oy釦 句C戸yr吋μ件-却-.i
D W阻 : 百lecontributionstothemeasuredconcentration
come仕omthewavelengthofthelaser，pa出 length，合加ge-shぜt
number，Gladstone-Dale constants，and molecular weight、as
showninEq.(5)._Thebiaslirnitasociatedwithpa出 leng血中ay
beat仕ibutedtothretypesoferors.(a)spatialerorin出eposi~on
of企剖i担nge邸s世白l低ati勾sdue旬todeflectionofcordinates，(b)concen住a包on actagainsteachothercreatingasma1circulationinthegasphase eror出atisdueto出ev紅 iation担 concentrationa1.ang.th:rayp~th just~ead of也efl釦 leleadingedgecreatingaflamablegas-air causedbydefl叫 叫 and(c)conce凶 ationeITor伽 tisduetothe rixtureoverthe剖 削edups位eamdirection.百1加'b叫u.1 changeinpa出 leng也.Amoredetai1eddiscusionisprovided戸 、ofaircirculationa1soincreasedintheups凶 amdirectionpreparing
Konishieta1.(197).Theprecisionandbiaslirnitsarel~sted in Table2.百letotaluncertaintyofDWHIisestimatedtobe:t15.9 percent.l
ResultsandDiscussion
LSPTResults. Figure3showsaschematicof出epulsating
flan，J.espreadconsisting'ofsixdiferentsteps.Figure4shows
(representative)photographsofgas-phaseSTTandliquid-phase
LSPTforfourdiferentsteps(a，b，c，叩dd). Figure5shows 1
two-dimensionalflowvectordiagramsforsteps(a，b，c，姐dd1). Step(a)isthebeginingofthecyc1eofpulsationand血 eproces movesontosteps(b)，(c)，(d1)，(d2)，(e)，andreturnstostep(a)to complete出ecyc1e.官 leschematicofstep(d1)，notshowninthe
JournalofHeatTransfer
forafast‘'jump"fiamespread(stepd1) toocur.Becauseofa sudeninc;e~s~ ofthefl~e-sp;eacÎ. rateatstep(d1)，theflame frontpushtheairinthecirculat.fonzonedes仕oying血ecirculation andcreatinganewairflowconcurentto也efl釘nespread.官 邸 concuITent厄r丑owacelerates出eliquid-surface-tensionflow，出e fiamespreadsalongwiththeflow，andeventua1ythefla皿 ealmost stopsafteritsleadingedgereachestheheadoftheliquidflow(step d2). A fewsecondslater，step(e)tokplace.τ'hentheproces returnedtostep(a)completingthe.cyc1e.σto，Masuda，叩dSaito， 191)providefiv
STTResults. Figures4(α)，(b)，(c)，and(d1) showsfourdiι ferentsmoke-s回 akphotographsforsteps(a，b，c，andd1) 紅 e
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