Available online at ScienceDirect. Procedia Engineering 150 (2016 )

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1 Avalable onlne at ScenceDrect Proceda Engneerng 15 (216 ) Internatonal Conerence on Indutral Engneerng, ICIE 216 Smulaton o Fuel Ignton Delay n Deel Engne wth Varou Fuel Feedng Sytem A.P. Senachn a, A.A. Korzhavn b, P.K. Senachn a, * a Altay tate techncal unverty named by I.I. Polzunov, 46, Lenn Avenue, Barnaul, Rua b Voevodky Inttute o chemcal knetc and combuton, Sberan Branch o the Ruan Academy o Scence, 3, Inttutkaya tr., 639 Novobrk, Rua Abtract A mathematcal model or numercal mulaton o the uel combuton delay n a deel engne a a problem o dynamc thermal exploon durng the adabatc compreon ha been etablhed. Ignton o uel and ar mxture n the local volume condered at multaneou evaporaton o drop and ga chemcal reacton wthn overall knetc. Satactory correlaton o computaton and expermental uel combuton delay on peed ablty and load ablty o the deel obtaned. Numercal modelng o pact o general knetc contant on the uel combuton delay carred out. The eature o el-gnton n the deel are condered at low value o chemcal reacton actvaton energy. 216 The Author. Publhed by by Elever Elever Ltd. Ltd. Th an open acce artcle under the CC BY-NC-ND lcene ( Peer-revew under reponblty o the organzng commttee o ICIE 216. Peer-revew under reponblty o the organzng commttee o ICIE 216 Keyword: Deel; uel; combuton delay; pontaneou gnton; chemcal reacton; overall knetc contant. 1. Introducton The uel combuton delay n the deel the mportant charactertc o the workng proce whch knowledge neceary at the engne degn tage. Combuton delay meaured expermentally on the tet deel or calculated wth the emprcal equaton whch uually look lke the equaton o O.M. Tode or the nducton perod o the adabatc thermal exploon (TE) [1, 2] n 1 1 Bp exp E RT, * Correpondng author. Tel.: E-mal addre: enachnpk@mal.ru The Author. Publhed by Elever Ltd. Th an open acce artcle under the CC BY-NC-ND lcene ( Peer-revew under reponblty o the organzng commttee o ICIE 216 do:1.116/j.proeng

2 A.P. Senachn et al. / Proceda Engneerng 15 ( 216 ) where B, n are emprcal coecent; p 1, T 1 preure and temperature at the tme o the begnnng o the uel njecton, correpondng to a crank angle (CA) 1 ; E - actvaton energy o overall reacton o uel gnton; R - unveral ga contant. We note that thee emprcal equaton have the nucent accuracy and lmted applcaton. We note that thee emprcal equaton have the nucent accuracy and lmted applcaton. It known that the workng body n the deel gnte rom compreon thereore the condered problem belong to the TE dynamc mode. In the aumpton o the homogeneou workng body, the problem o combuton delay n the deel, on the ba o reult o work [3], apparently, or the rt tme n the theoretcal plan olved n work [4, 5]. A a reult o the analy t obtaned, or the nu mechanm V Vc rfp 1 co the condton o el gnton or crtcal preure P p p1 n the ytem (or range o preure P Pmax ): 1 * 1 1 P * * QC T k p RT P E exp P 1 RT 2n 1 1 a 1 P P * , (2) e P arcco 1, 2n 2n 2n 1 P p, max max 1 p1 where Vc - volume o combuton chamber; Fp D - pton area; r - crank radu; e =2, ; 12rFp Vc - geometrc compreon rato; 1 - compreon rato ater CA 1 ; n - crankhat requency; - ar exce coecent; a - tochometrc concentraton o uel n the homogeneou mxture wth ar; k, - pre-exponental actor o the rate contant and total order o chemcal reacton o el gnton; CP CV - rato o thermal capacte; Q - molar heat releae o the uel. Subcrpt 1 apple to the tme o the uel njecton begnnng. Depte mplcty o the mathematcal model oered n [4, 5], the analytcal oluton o the problem on crtcal condton o mxture el gnton due to compreon (2) obtaned relect correctly phycal and chemcal procee o uel gnton n the deel and even t may be recommended to practcal ue. However real proce o gnton n the deel much more dcult than proce o gnton o a homogeneou mxture at adabatc compreon. We wll ormulate the peced mathematcal model whch ome hypothee are preented n [6, 7]. 2. Mathematcal model or the local volume We beleve that the ratonal problem denton may be baed that the deel torch gnted wth ome elgnted local volume () that located near an external urace o the uel jet [6, 7]. Th ormed practcally at the tme o the begnnng o uel njecton 1 rom the mallet drop evaporatng n the coure o urther compreon. The problem reduced to ndng o the gnton delay (the nducton perod) o th. In addton or we accept: 1. the drop whch are n evaporate due to nternal energy o whch urther up to el gnton doen't exchange energy and ma wth urroundng ga and other drop whch are both out o and n the uel torch; 2. only one ormed that doen't reduce a problem generalty (a t poble to change ntal condton o el gnton n th ); 3. we uppoe that drop n at the moment 1 ntantly heat up rom uel upply temperature T to bolng temperature T due to nternal energy o and then gradually evaporate and el gnton occur n ga phae o. 2 4

3 192 A.P. Senachn et al. / Proceda Engneerng 15 ( 216 ) Intal compoton o an ar charge A a reult o tandard calculaton at the tme o clong o the nlet valve a we have: oxygen - 1a, ntrogen - 2a, vapor o water- 3a, argon - 4a and doxde carbon - 5a o mole. Then untl to the begnnng o uel njecton 1 the total number o mole o an ar charge a, oxygen part and other component a ja takng nto account the tate equaton at the tme o clong o the nlet valve, wll be a pv RT, a a a a ja j1 5 a 1a 1a, pv a a RTa a ja ja. (3) pv RT a a a 2.2. Local volume In or whch the tate equaton at ntal and current moment gven by 5 1 j j1 pw R R R, (4) 6 j j1 pw R R 1m M R, (5) there proceed an overall reacton o el gnton on the chemcal equaton or ome mxture uel (whch condtonal molecule CHO c h o nclude c - atom o carbon, h - atom o hydrogen and o - atom o oxygen) c h o CHO ch o O cco h HO, 6) at that new component o the mxture n aren't ormed a n product o reacton there are only water and carbon doxde. Here n (4) t arbtrarly (or dentene) accepted that at the tme o the begnnng o uel upply (CA 1 ) cont o one mole o the ubtance n the ga phae ncludng ve component (vapor o uel n the ga phae are abent): a, 1 1a a, 2 2a a, 3 3a a, 4 4a a, 5 5a. (7) 6 We wll be et by n advance unknown coecent o ar exce n (t the vared parameter n the model), whch would take place all lqud uel n evaporated ntantaneouly at the tme o crank angle 1. Takng nto account (6) and that ater evaporaton o uel drop n the ar exce coecent n t wll accept preagned value, we have 1 m h o c M 4 2, rom (7) we nd ma o lqud uel m n at the moment 1, namely

4 A.P. Senachn et al. / Proceda Engneerng 15 ( 216 ) m M 1 M a1 a. (8) ch 4o 2 ch 4o 2 The ntal temperature o the mxture at once ater the moment o the begnnng o uel upply ounded rom the energy (enthalpy) balance equaton or one mole o ga, takng nto account lqud uel drop heatng up (or drop) rom temperature o uel upply rom the nozzle T to the bolng temperaturet, that T m C T T M C, (9) 1 1 p where Cp Cp the ntal molar heat capacty o the ga n ; C p the molar heat capacty o the ga urroundng the uel jet. Ma uel evaporaton rate n takng nto account average eectve dameter drop and average ma m ( 6), wll be a [8] drop 3 drop m 3NugM m 1 2 m ndrop L m 13 T, (1) where m dm d the dervatve on crank angle. Chemcal reacton rate n the ga phae n decrbed by the overall knetc equaton 2 W k A A 6 1 exp E R, (11) where A6, A 1 - concentraton o uel vapor (j=6) and oxygen (j=1). The rate on mxture component or oxygen (j=1), ntrogen (j=2), water vapor (j=3), argon (j=4), carbon doxde (j=5) and uel vapor (j=6) wth takng nto account (5) wll be: h o W h 1 c W, W2, W3 W, W4, W cw, W6 W. At that the ummary quantty o mole n Rate o concentraton change o the mxture component n wth takng nto account procee o evaporaton and uel el gnton accordng to the equaton o overall knetc (6), n cae o varable temperature and preure wll be [9] W h o p R A1 c A 1 W j 2n 4 2 p 2np j, (12)

5 194 A.P. Senachn et al. / Proceda Engneerng 15 ( 216 ) W p R m6 p A6 A 6 W j 2 n p 2np j M R (13) and rate o mole number change o the mxture component n, takng nto account (6), wll be h or 1 Wc 4 22 np, (14) 2, (15) 3 h R W, (16) 2 2 np 4, (17) 5 R W, (18) 2 np 6 R m W. (19) 2 np M The equaton o energy or the mxture n may be repreented a the dependence 6 CP p j jw h o H j m 1 Cp6 T L. R p j1 R 2n p 4 2 RM (2) 3. Mathematcal model o n-cylnder proce A noted above the local volume mall n comparon wth cylnder volume thereore the chemcal reacton o el gnton that occur n t ha no nluence on preure dynamc n the cylnder o the engne. We alo neglect the volume o lqud uel compare wth the volume o the ga phae. The ytem o equaton o the el gnton proce o n the combuton chamber volume along wth (3)-(5), (7)-(2) nclude the equaton: o dynamc o the ytem volume (or the axal mechanm) V V c 1 co n 1, (21) n o the law o lqud uel upply (or 1 1 z ) m m, (22) z z (here, m - duraton and ma o cycle uel upply). z z

6 A.P. Senachn et al. / Proceda Engneerng 15 ( 216 ) o uel evaporaton rate (wth takng nto account the evaporaton eectvene actor due to dect hot ga phae n the uel jet 1; n computaton t uually aumed k.5 ) [8] k 3 M m k m T T, (23) g Num 2 n a L where a - mean eectve dameter o a uel drop n a jet; n computaton t uually wa accepted o tate o the ar charge (the general mxture, wthout dvon nto uel jet and ar charge) a, drop pv m m 5 j RT, (24) j1 M j M o preure dynamc (energy o the overall mxture) n the cylnder, takng nto account heat exchange procee wth wall and uel drop and ma exchange wth evaporatng uel drop n the uel jet, p p k Tk T m pv pv C T T Cp T T L k 2 C C m 1. (25) R R n M M A a reult o ntegraton o the ytem o equaton (5), (1)-(25) wth ntal condton (3), (4), (7)-(9) wth Runge-Kutt' method o the ourth order wth own computer code [1], developed n algorthmc language C wth ung compler Lnux, by mean o derental crteron o el gnton [3] dln dln p 1, p p 1, we ound o uel gnton n the deel. Thu n th problem we nd the combned uel gnton delay that untng the phycal delay (evaporaton o uel drop n ) and the chemcal delay (el gnton n o the mxture) a both procee occur multaneouly. 4. Ignton delay n deel at uel upply wth ndvdual njector. Determnng o knetc o deel uel Expermental data on uel gnton delay are obtaned rom ndcator dagram n the condton o actory tetng on peed and adjutng ablte o ngle-cylnder deel ntallaton by dmenon 13/14 [7]. At uel upply wth ndvdual njector the njecton preure uually equal 2-4 MPa (n our tet t wa near 3 MPa) Aement o the actvaton energy A the thermodynamc model o deel uel there condered the mxture uel contng o 5% cetane C16H 34 and 5% o 1 methyl naphthalene C11H 1 that burn on the overall knetc equaton (6). For the numercal oluton o the problem o gnton delay t neceary to know overall knetc contant n the equaton (11), namely, energy o actvaton E, a pre-exponental actor o the rate contant k and an overall order o chemcal reacton. Thee contant or deel uel are known now wth the nucent accuracy that doen t allow tartng drectly numercal modelng o the problem. We wll note that n emprcal equaton o the type o derent author or calculaton o deel uel gnton delay there are accepted a the actvaton energy E and an overall order o reacton 1 n the numercal value gncantly derng rom each other [11] (Table 1). Other problem o the electon o overall knetc contant cont n that both or lght and or heavy hydrocarbon the overall knetc o el gnton remarkable that actvaton energy n the temperature range o

7 196 A.P. Senachn et al. / Proceda Engneerng 15 ( 216 ) K ha qute harp break o the curve. More detaled conderaton o th temperature range how that actvaton energy there very uncertan value [12]. That behavor o the reacton actvaton energy n trantonal temperature range apparently connected wth the two tage o el gnton o the hydrocarbon that noted repeatedly by derent author. Accordng to the equaton The actvaton energy can be ound rom the dagram o dependence o the uel gnton delay on the nvere temperature lg (1 T ). For example the analy o expermental data on gnton delay o the deel uel that receved n the contant preure bomb p cont how that or the hgh-temperature range E=25 kj/mol, and or the low-temperature about 9 kj/mol [13]. In [11] cloe data are provded or hgh-temperature range o 2514 J/mol, or low-temperature 7667 J/ mol. A at el gnton the thermodynamc tate o the mxture contently pae the range rom low temperature to hgh one ncludng trantonal range t neceary to nd out alo nluence o actvaton energy value on the uel gnton delay n a deel. At numercal modelng at the rt there wa accepted very low actvaton energy o E=2514 J/mol that charactertc or hgh-temperature range [12] and nluence o ar exce coecent n the local volume on the uel gnton delay wa condered. Numercal modelng o the uel el gnton proce n located on external border o the uel jet wa carred out a ollow. For =1 on the gnton delay that known rom the expermental data ( =9.5 o CA) obtaned on ngle-cylnder ntallaton the eectve rate contant o the overall reacton wa ound at the order o reacton =1.5. Further or th rate contant the ar exce coecent n wa vared. Calculaton how that at ncreae n the gnton delay at rt decreae and then lowly ncreae. The mnmum correpond =1.35 (Fg. 1, the bottom curve). Then or the new ar exce coecent n =1.35 the new eectve rate contant wa ound at the reacton n conrmed order o 1.5 or the ame expermental data. Thu the varaton o the ar exce coecent extence o a mnmum o the delay at =1.35 (Fg. 1, top curve). Smlar calculaton were carred out or actvaton energy o E=7667 J/mol that charactertc or lowtemperature range. At the varaton o ar exce coecent n there wa obtaned the mnmum at the value =1.19. For th value t wa ound new rate contant and we made ure o extence the mnmum at =1.19. Table 1. The knetc contant accepted n emprcal equaton [11]. Author (author) o the emprcal equaton The accepted value o actvaton energy,, J/mol Value o a barc exponent, B. Kncht 386 -,39 1,39 F. Strnger 455 -,76 1,76 H. Fujmoto ,6 2,6 F. Schmdt ,8 2,8 H. Voler 3866 (379) -1,19 2,19 G. Hroyau, T. Kadota and M. Ara 653-1,23 2,23 R.Z. Kavtoradze ,3 2,3 M. Tuge 171-1,66 2,66 L. Spadachny, J. Te Velde 174-2, 3, N Correpondng order o reacton, Numercal modelng how that the varaton o actvaton energy over a wde range at the contant order o chemcal reacton =1.5 allow to nd dependence o optmum o the ar exce coecent n (correpondng to the mnmum o gnton delay). At ncreae n actvaton energy E rom 2514 to 7667 J/mol the optmum ar exce coecent n decreae monotonouly rom the value o 1.35 to At that pre-exponental actor o

8 A.P. Senachn et al. / Proceda Engneerng 15 ( 216 ) the rate contant o the overall reacton correpondng to the optmum value o grow monotonouly rom the value to mol -.5 m Fg. 1. Dependence o uel gnton delay n the deel on ar exce coecent n at actvaton energy o E=2514 J/mol and the order o chemcal reacton o =1.5:1- =1., k = ; 2- =1.35, k = mol -.5 m Fg. 2. Dependence o uel gnton delay n the deel on ar exce coecent n at actvaton energy o E=38 J/mol and the order o chemcal reacton o =2.5: 1- =1.5, k = ; 2- =1.4, k = mol -.5 m At nal choce o the value o eectve actvaton energy o chemcal reacton, apparently t poble to chooe the value o E=38 J/mol beng average value between low-temperature and hgh-temperature range (Fg. 2, Table 1) that charactertc or trantonal range. For actvaton energy o E=38 J/mol and the overall order o reacton o =1.5 the dependence o uel gnton delay on ar exce coecent n are mlar to the dependence obtaned or hgh-temperature E=2514 J/mol and low-temperature E=7667 J/mol range. The mnmum take place at =1.3 (Table 2). Table 2. The knetc contant accepted n emprcal equaton [11]. Compreon rato, Rotaton requency, n, mn -1 delay, CA. Value o the knetc contant Optmum value exper. calculaton, J/mol k, (mol,m,) ,

9 198 A.P. Senachn et al. / Proceda Engneerng 15 ( 216 ) So or any expermental pont (or example, or n =13 mnute -1 ) at the et compreon rato =15.5 ater the choce o ome actvaton energy value o (or example, E=38 J/mol) a a reult o numercal calculaton t poble to nd ar exce coecent that =1.3 correpondng to the mnmum gnton delay and then numercal value o pre-exponental actor o the rate contant k that mol -.5 m (Table 2). It n addton poble to plot dagram o dependence o ntal and end temperature o the mxture on (Fg. 3) whch are practcally concde wth each other. At ncreae the ntal temperature o the mxture beore el gnton grow (Fg. 3, curve 1) and end one ater el gnton all (Fg. 3, curve 2). At that n the range o change n rom 1.19 to 1.35 the end temperature o the mxture n (ater el gnton and combuton) ucently hgh to gnte the uel and ar torch (Fg. 3). Bede, the analy o a number o emprcal equaton on uel gnton delay how [11] that n them or deel uel the value o a barc exponent correpondng to the order o reacton 1 n wthn (Table 1) accepted. Thereore numercal reearch o nluence o an order o reacton on the tangent o nclnaton angle o the peed ablty wa carred out ( n ). At plottng o the peed ablty o uel gnton delay n the deel ( n ) t turn out that, except a tartng pont at n =13 mnute-1 all other calculated pont won't rather well be agreed wth experment (or maller value o rotaton requency they are lower expermental, and or the hgh are above). That the tangent o nclnaton angle o the theoretcal dependence ( n ) plotted n g. 4 doen't correpond to expermental value (Table 2). At that numercal calculaton how that the varaton o the value o actvaton energy o E n the range rom 2514 to 7667 J/mol doen't nluence on the tangent o nclnaton angle o the peed ablty ( n ). There appeared an aumpton that the numercal value o an overall order o chemcal reacton o =1.5 accepted by u n't the optmum one. Numercal calculaton at change o an order o reacton toward ncreae how that the tangent o nclnaton angle o the peed ablty ( n ) decreae and at the value o =2.5 correpondng wth expermental data (Table 2, Fg. 4). Further or actvaton energy o E=38 J/mol by mean o varaton n the we nd the mnmum o uel gnton delay at the value o =1.4 (Fg. 2, bottom curve). For th value we nd a new pre-exponental actor o a rate contant o overall chemcal reacton o k= mol 1.5 m and we make ure o occurrence o the mnmum at =1.4 (Fg. 2, top curve). A expected the dependence obtaned are mlar thoe plotted n g. 1 (Table 2). Fg. 3. Dependence o the mxture temperature n on ar exce coecent, actvaton energy E and the reacton order (t obtaned by mpong o a number o dependence): 1 ntal temperature n ; 2 end temperature n Fg. 4. Dependence o gnton delay n the deel on the rotaton requency o the cranked hat at =2.5, E=38 J/mol, k = mol m 4,5-1, =15.5 and Dahed lne experment, contnuou calculaton

10 A.P. Senachn et al. / Proceda Engneerng 15 ( 216 ) Modelng o uel gnton delay n the deel wth ytem o uel upply o an elevated preure o lke Common Ral (CR) Expermental data on uel gnton delay n the deel wth uel upply ytem lke CR are obtaned n AltSTU (Barnaul, Rua) rom proceng o ndcator dagram o ull-cale tet on ngle-cylnder deel ntallaton by dmenon 13/14 [14, 15]. Fgure 5 how the nluence o ar exce coecent n on the uel gnton delay. Though qualtatve nature o dependence reman (Fg 1 and 2) that at ncreae rom the value o 1. the charactertc mnmum oberved however t very poorly expreed thereore n practcal calculaton or the deel wth uel upply ytem lke CR t poble to aume =1. wthout prejudce to accuracy. Calculaton are carred out or the overall knetc wth reacton order o =2, actvaton energy o E=38 J/mol and the rate contant k = mol -1 m 3-1. Fg. 5. Inluence o ar exce coecent n on the uel gnton delay Fg. 6. Comparatve peed ablty o the gnton delay at the uel njecton preure p ng=9 MPa: pont expermental data; dotted lne the trend lne; the contnuou lne numercal modelng Fg. 7. The peed ablty o the gnton delay at the njecton preure o p ng=15 MPa: pont expermental data; dotted lne the trend lne;the contnuou lne numercal calculaton

11 2 A.P. Senachn et al. / Proceda Engneerng 15 ( 216 ) Fg. 8. The load ablty o the gnton delay at the njecton preure o p ng=6 MPa and requency o rotaton n=17 mn -1 : pont expermental data; dotted lne the trend lne; the contnuou lne numercal calculaton In gure 6 and 7 reult o numercal modelng o the uel gnton delay are gven n peed ablty charactertc wth the uel njecton preure p nj equal to 9 and 15 MPa repectvely n comparon wth the expermental data obtaned on the ngle-cylnder ntallaton. From the g 6 and 7 t een that complance o expermental and calculated uel gnton delay on peed ablty are qute atactory. The greatet dperon o expermental pont take place on the load ablty (Fg. 8) correpondngly the reult o numercal modelng o the uel gnton delay have more devaton rom expermental value (but they can alo be condered a atactory). 5. Feature o el gnton n the deel at low actvaton energy o chemcal reacton A t wa noted above, at many hydrocarbon, epecally wth heavy molecular weght, proce o el gnton take place n two tage and at temperature o 7-9 K th proce ha very uncertan value o actvaton energy [12] at that rather low value (down to zero value). It connected wth accumulaton and then decompoton (at thee temperature) hydroperoxde manly H 2 O 2. Th crcumtance may reult n gncant ncreae n chemcal reacton rate at thee temperature and at el gnton o heavy hydrocarbon to ht th maxmum n area o rch mxture depte conderable coolng o the mxture becaue o evaporaton o lqud uel drop. A Charle K. Wetbrook note (Wetbrook Charle K. 2) n the proceedng o the nternatonal ympoum on combuton [16] deel engne ext already many year but untl recently the bac phycal and chemcal prncple o combuton n the deel weren't adequately undertood. Further he note that rather recently n the ere o proound tude wth laer dagnotc J.E. Dec (Dec J.E. 1997) preented the clear el-content pcture o combuton n the deel [17]. H reult how that the uel jet quckly evaporate and mxe up wth the hot compreed ar. An ar exce coecent and temperature o beng ormed mxture ncreae multaneouly. The mxture tart to react. By reult o Dec' obervaton th mxture gnte at the very low ar exce coecent o about =.25. Th large-cale problem o gnton wa analyzed wth ue o detaled chemcal knetc [18]. The premxed area tart to react when the ar exce coecent o reache =.1 though chemcal reacton rate at the begnnng very low. In the progre o the mxng proce and temperature growth the reacton rate grow. Fat reacton begn when temperature o the mxture become about 7 K. The mechanm o gnton o the mxture dentcal to the mechanm or any other hydrocarbon (through accumulaton, and then decompoton o H 2 O 2 whch oberved at reachng o ome rather hgh temperature). Thu the knetc mechanm o gnton n the deel dentcal to that mplemented n rapd compreon machne (RCM) and at knock n the engne wth park gnton. The man derence that gnton n the deel take place n the condton o very rch uel mxture. The concluon o author o above mentoned work that gnton take place n the condton o very rch uel mxture n't conrmed by our reearche (Fg. 9-11). The dependence obtaned by u tety accurately that gnton take place n poor mxture at the ar exce coecent cloe to tochometrc one at ome ht n area o poor mxture ( = ). It alo conrmed by the plot o ntal mxture temperature veru ar exce coecent (Fg. 12). The matter that ormaton o rch uel mxture rom evaporatng drop requre conderable

12 A.P. Senachn et al. / Proceda Engneerng 15 ( 216 ) energy whch couldn't be taken other than rom the ar. Thereore ntal temperature o the rch mxture very low or el gnton o the condered volume o the mxture (Fg. 12). On the other hand accordng to the knetc equaton (6) or heavy hydrocarbon to whch deel uel (DF) belong mxture ht n rom tochometrc to rch area, or example, to =.5 wll brng about to ncreae n the reacton rate approxmately twce. Th eect epecally brghtly ha to become apparent at the very low actvaton energy about 4 J/mol and le that n't generally charactertc or combuton procee (wth the value o actvaton energy o =8-17 J/mol). Thereore, takng nto account work o oregn author [16-18] we conducted reearche o el gnton o DT n at the expanded range o the ar exce coecent or derent value o actvaton energy o chemcal reacton. Once agan we note that ambguty o a choce o actvaton energy E that nluencng on eature o phycal and chemcal proce o uel el gnton one o bac dculte o theoretcal determnaton o the uel gnton delay n the deel. Actvaton energy. Modelng o uel gnton delay carred out n work [7, 14] wth the actvaton energy equal to 2514, 7667 and 38 J/mol at ar exce coecent n >1 on the ba o expermental data howed the next. At the overall order o the reacton by varaton o a a reult o oluton o the nvere problem the overall knetc contant obtaned decrbe well the value o the perod o nducton (the uel gnton delay) on peed and load ablty o the engne ncludng at change o geometrcal compreon rato. Though n the nal veron t wa accepted o actvaton energy o E =38 J/mol, but t wa the arbtrary decon a the preerence wa unevdent. Addtonal calculaton o the el gnton proce o the mxture n n the deel on the equaton gven above at varaton o ar exce coecent ncludng area o rch mxture howed the ollowng [19]. Fgure 9 how the dependence o ntal temperature o the mxture and end temperature o the combuton product e on the ar exce coecent n. A t een rom the plot at <.3 ntal temperature o the mxture lower 6 K (becaue o energy conumpton on uel evaporaton) that reult n ncreae n the uel gnton delay. And condton o gnton o uel torch wth combuton product o the mxture n (not lower than 17 K) lmt the poble value o n the range rom.55 to Fgure 1 how dependence o the uel gnton delay n on the ar exce coecent at actvaton energy 9 o the mxture o E=38 J/mol, 1.5 and k mol -.5 m The rate contant obtaned or the expermental pont (g. 1, black crcle) at the condton o =1.. It een extence o two mnma (g. 1, lght trangle) one n rch mxture =.45 and another that le deep n poor area =1.5. At that the maxmum o ntal chemcal reacton rate n (g. 1, lght quare) take place alo n rch area. Thu, takng nto account g. 1 t poble mxture gnton n at =.55 that atactory agreed wth Dec' reult (Dec J.E. 1997) [17]. In gure 11 and 12 there are dependence o the uel gnton delay n on the ar exce coecent or actvaton energy o the mxture o E=7667 and E=12 J/mol repectvely. From gure 11 t een that mlar to g. 1 there are two mnma o the uel gnton delay (g. 15, lght trangle) o rch =.85 and poor =1.15 that are tuated ymmetrcally relatve to tochometrc compoton o the mxture =1 and approxmately the dentcal depth o t dcult to gve preerence any o them. At that the maxmum o ntal chemcal reacton rate jut between mnma (g. 11, lght quare) near concentraton =1. From g. 12 t een only one mnmum o the uel gnton delay n poor area =1.6 (g. 16, lght trangle). At that the maxmum o ntal chemcal reacton rate jut at =1.6 (g. 12, lght quare). Thu takng nto account g. 9 mxture gnton n poble at =1.25 that not agreed wth Dec' reult (Dec J.E. 1997) [17] but doen't contradct our work [7, 14, 19].

13 22 A.P. Senachn et al. / Proceda Engneerng 15 ( 216 ) Fg. 9. Dependence o ntal and end e temperature o the mxture n on the ar exce coecent. 1 ntal temperature; 2 end temperature; 3 - temperature retrcton on the condton o uel torch gnton. Fg. 1. Dependence o the uel gnton delay n the deel on n at actvaton energy o E=38 J/mol (=1.5): 1 - gnton delay; 2 - ntal chemcal reacton rate; 3 - product o concentraton o uel and oxdzer. Fg. 11. Dependence o the uel gnton delay n the deel on n : E=38 J/mol, =1.5 and k = mol -.5 m (degnaton n gure 14). Fg. 12. Dependence o the uel gnton delay n the deel on n : E=12 J/mol, =1.5 and k = mol -.5 m (degnaton n gure 14). 6. Concluon 1. It ormulated phycal and t contructed mathematcal model o uel el gnton n the deel. The computer program or numercal modelng o gnton delay n the deel developed.

14 A.P. Senachn et al. / Proceda Engneerng 15 ( 216 ) Numercal modelng o the drect and nvere problem o dynamc o el gnton n the deel and on the bae o own expermental data there wa carred out reearche o overall knetc contant o deel uel and the dependence o the gnton delay n the deel on the proce parameter accordng to peed and load ablte o the engne. 3. At ncreae o uel njecton preure p nj the gnton delay, a a whole, decreae becaue o ncreae n nene o uel atomzng (reducton o average dameter o drop) that reult n reducton o phycal and um component o gnton delay n the deel. 4. Mode o uel gnton n the deel n the area o very rch mx =.5 (but not below) can be realzed on heavy uel at low actvaton energy E about 4 kj/mol that n't charactertc or clacal problem o the combuton theory. 5. On the ba o own and lterature normaton we may clam that n the deel uel el gnton happen at mxture concentraton cloe to tochometrc one wth ht n poor area (at 1.5< <1.25) wth actvaton energy o the overall reacton E n the range o J/mol. 6. The concluon o author o work [17-19] that el gnton n the deel happen n the condton o rch mxture n't probably nal. The problem demand urther expermental and theoretcal tude wth ue o detaled knetc o chemcal reacton. Reerence [1] O.M. Tode, Adabatc thermal exploon, Zhurnal zcheko khm. 4 (1933) (n Ruan). [2] O.M. Tode, The theory o thermal exploon, Zhurnal zcheko khm. 13 (1939) (n Ruan). [3] P.K. Senachn,V.S. Babkn, Sel-Ignton o Ga n Front o the Flame Front n a Cloed Veel, Comb. Explo. and Shock Wave. 18 (1982) 15. [4] P.K. Senachn, R.Kh. Abdulln, V.S. Babkn, Analy o el gnton n deel, Combuton phyc and method o t reearch, Interunverty collecton, Publhng houe o Chuvah State Unverty, Chebokary. (1983) 553. (n Ruan). [5] D.D. Matevky, P.K. Senachn, Fuel gnton delay n the deel a the perod o nducton o dynamc thermal exploon, New o hgher educaton nttuton, Mechancal engneerng. 46 (1995) (n Ruan). [6] D.D. Matevky, P.K. Senachn, A.P. Senachn, Modelng o a delay o gnton o uel n the deel, Polzunovky vetnk. 3 (21) (n Ruan). [7] A.P. Senachn, A.A. Korzhavn, P.K. Senachn, Denton o global knetc o deel uel by the numercal oluton o the nvere problem o dynamc o el gnton n the deel, Polzunovky vetnk. 4 (29) (n Ruan). [8] S. Kumaga, Combuton, Chemtry, [9] Yu. Varnat, Modelng o combuton procee by mean o detaled knetc o elementary reacton, Chemcal phyc. 3 (1994) 316. [1] A.P. Senachn, P.K. Senachn, RU Certcate o tate regtraton o the computer program (211). [11] R.Z. Kavtaradze, Theory o pton engne, Specal chapter, The textbook or hgher educaton nttuton, MSTU publhng houe, Mocow, 28. (n Ruan). [12] U. Phahl, K. Fweger, G. Adomet, Ignton o Del-Relevant Hydrocarbon-Ar Mxture Under Engne Condton, n: Proceedng o Twenty-Sxth Sympoum (Internatonal) on Combuton, The Combuton Inttute. (1996) [13] A.N. Vonov, Combuton n hgh-peed pton engne, Mechancal engneerng, Mocow, (n Ruan). [14] A.P. Senachn, P.K. Senachn, Fuel gnton delay n the deel wth ytem o uel eedng o an elevated preure, New o the Samara Ruan Academy o Scence centc center. 13 (211) [15] A.P. Senachn, P.K. Senachn, Modelng o uel gnton o n the deel, The Meenger o the Sberan Oce o Academy o Mltary Scence. 1 (211) (n Ruan). [16] C.K. Wetbrook, Chemcal knetc o hydrocarbon gnton n practcal combuton ytem, Proceedng o the Combuton Inttute. 28 (2) [17] J.E. Dec, A conceptual model o DI deel combuton baed on laer-heet magng, SAE paper. (1997). [18] P.F. Flynn, R.P. Durrett, G.L. Hunter, O.C. Aknyem, J.E. Dec, C.K. Wetbrook, Deel Combuton: An Integrated Vew Combnng Laer Dagnotc, Chemcal Knetc, and Emprcal Valdaton, SAE paper. (1999). [19] A.P. Senachn, V.A. Sntyn, The problem o a choce o actvaton energy o global chemcal knetc at numercal modelng o uel el gnton o n the deel, Scentc problem o tranport o Sbera and the Far Eat. 2 (211) (n Ruan).