DEVELOPMENT OF MODEL FOR RUNNING DIESEL ENGINE ON RAPESEED OIL FUEL AND ITS BLENDS WITH FOSSIL DIESEL FUEL

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1 ENGINEERING FOR RURAL DEVELOPMENT Jlgava, DEVELOPMENT OF MODEL FOR RUNNING DIESEL ENGINE ON RAPESEED OIL FUEL AND ITS BLENDS WITH FOSSIL DIESEL FUEL Ilmars Dukuls, Avars Brkavs Latva Uvrsty of Agrcultur Abstract. Usg ExtdSm smulato softwar a mathmatcal modl s dvlopd to dtrm th dsl g opratg paramtrs usg rapsd ol ad ts blds wth fossl dsl ful. Th ma dffrc of th modl from othr studs: dvlopd modul for dtrmato of th ambt tmpratur wh, usg rapsd ol ful, fossl dsl has to b addd to sur th ful pump oprato ad ful flow through th systm; dvlopd aalytcal rlatoshps to dtrm th rsdual gas molar calorfc valu, that provds cotuous modllg procss; spcfd mprcal coffcts for costructg of g powr curvs. Th modllg rsults show that usg pur rapsd ol vhcls ca b opratd up to -4 ºC, wth a bld RO8 (8 % rapsd ol ad % fossl dsl ful) up to -7 ºC ad so o. If th ambt tmpratur drops blow -3 ºC, blds wth rapsd ol cott of lss tha 3 % or pur dsl ful hav to b usd. Th rducto of th g powr ad torqu for th car VW Golf III.9TD g s lar ach % of rapsd ol ful bld rducs th maxmum powr ad torqu of aroud.5 %. Usg pur rapsd ol th dcras s about 5 %. Kywords: rapsd ol ful, fossl dsl ful, modllg, g powr, g torqu. Itroducto Th am of th rsarch s to dvlop a mathmatcal modl to dtrm th ma dsl g opratg paramtrs rug thm o rapsd ol ad ts blds wth fossl dsl ful, as wll as to stablsh sutabl rapsd ol ad fossl dsl ful bld ratos, opratg motor vhcls at dffrt ambt tmpraturs, cludg th os that ar mt Latva wtr codtos. Matrals ad mthods Aalyzg th smulato tools sutabl for modllg of motor vhcl opratg paramtrs th ExtdSm softwar s slctd. Th dvlopd modl cossts of thr parts or moduls (Fg. ). Fg.. Modl block dagram Th frst modul dpdg o th ambt tmpratur dtrms f motor vhcls ca b opratd o pur rapsd ol, or ol should b mxd wth fossl dsl ful. Th put paramtr of th scod modul s th ful cott ad proprts. Dsl g oprato thrmodyamc calculato s basd o th mthodology approvd at svral doctoral thss [; ], addto cratg aalytcal rlatoshp to dtrm th rsdual gas molar calorfc valu that provds a cotuous modllg procss. A aalogu of th thrd modul s foud th thss Applcato of bothaol Otto gs [3]. Whl thr th ptrol powrd g oprato s modlld, th algorthm s sutabl also for dsl gs spcfyg th coffcts for costructg of th g ffctv powr ad torqu curvs. 39

2 ENGINEERING FOR RURAL DEVELOPMENT Jlgava, To sur th ful pump oprato ad th ful flow th ful supply systm, ful kmatc vscosty should ot xcd 5 mm s - [4]. I th modl as a crtcal th lowst valu s assumd to hav a small marg of safty oprato of th motor vhcl durg th wtr tm. To dtrm th kmatc vscosty of ful dpdg o th ambt tmpratur, th followg formula s usd [5]: whr v kmatc vscosty of ful, mm s - ; T ambt tmpratur, K; A, B ad C coffcts that dpd o th usd ful. B C l( v ) = A + +, () T T To dtrm th coffcts th xprmtal studs prformd Spa ar usd [6]. Th coffcts for fossl dsl ful (DF) ad rapsd ol (RO) ar obtad usg rgrsso aalyss (Fg. ). Natural logarthm of th ful kmatc vscosty l(v) y = x x +.53 R = y = x x -. R = Th ambt tmpratu vrs valu T -, K - Fg.. Dtrmato of coffcts for calculatg of ful kmatc vscosty Th valus calculatd usg th obtad formula ar compard wth othr studs, for xampl, wth th masurmt of th kmatc vscosty of rapsd ol at tmpratur rag K ( ºC) carrd out Grmay [7]. Kmatc vscosty of ths study corrspods to th valus obtad by aalytcal mthods, so th followg rlatoshps ar usd th modl: A + whr v th -ful kmatc vscosty, mm s - ; t ambt tmpratur, ºC; A, B ad C th -ful coffcts. B + C ( t+ 73 ) ( t+73) v =, () Dpdg o th ful cott th wghtd avrag kmatc vscosty of th ful bld s calculatd. Th modl blocks for dtrmato of th ful kmatc vscosty ar show Fg. 3. If th ful bld prctag s kow, th cott of carbo (C), hydrog (H) ad oxyg (O) cott ful bld ful mass fractos ca b calculatd from th rlatoshps: C C sat =, m m H H sat m =, whr m th -ful cott bld, mass %; C sat- cott of carbo th -ful, mass parts; H sat- cott of hydrog th -ful, mass parts; m O sat = DF RO O m, (3) m 3

3 ENGINEERING FOR RURAL DEVELOPMENT Jlgava, O sat- cott of oxyg th -ful, mass parts. Th calculatd C, H ad O valus srv as outputs to th scod modul of th modl Dsl g oprato thrmodyamc calculato (Fg. 4). Fg. 3. Modl blocks for calculato of ful kmatc vscosty Fg. 4. Ful bld cott dtrmato blocks Th thrmodyamc calculato of dsl g oprato s basd o th classc rlatoshps, gv varous sourcs of formato [; ; 8-]. I som of thm rsdual gas molar hat capacty calculato dpdg o th tmpratur ad ar-ful rato s basd o th trpolato mthod aftr th mprcal data ar rad from th tabl. It dos ot provd a cotuous modllg procss, as at crta modllg stps a umbr of paramtrs hav to b trd maually. Thrfor, to gt th rsdual gas molar calorfc valu aalytcal rlatoshp s workd out. Dsgg of rsdual gas tmpratur ad molar calorfc valu corrlato dagrams at dffrt ar-ful ratos, rgrsso quatos ad coffcts of dtrmato ar foud. Howvr, drct troducto of ths quatos th modl s ot approprat, bcaus t lads to th us of a umbr of logcal oprators. Bsds, th calculato would b corrct th cas of th ar-ful rato trmdat valus such as.3,.56, tc. Thrfor, aothr rgrsso aalyss s prformd to dtrm whthr thr s a corrlato btw rsdual gas molar calorfc valu dcras wth crasg th ar-ful rato. 3

4 ENGINEERING FOR RURAL DEVELOPMENT Jlgava, At ach ar-ful rato calculatos wr mad usg th formula: K dcras Q Q =, (4) whr Q rsdual gas molar calorfc valu at costat tmpratur ad ar-ful rato, kj (kmol K) - ; Q rsdual gas molar calorfc valu at th sam tmpratur ad ar-ful rato α, kj (kmol K) - ; umbr of dffrt costat tmpraturs, whr th calculatos wr mad ( =, t = ºC, stp ºC). Th corrlato dagram of molar rsdual gas calorfc valu rducto dpdg o th ar-ful rato s gv Fg y =.335x -.547x +.55 R =.998 K dcras Fg. 5. Corrlato dagram of rsdual gas molar calorfc valu rducto dpdg o ar-ful rato Th fal rlatoshp troducd to th modl s obtad combg both rgrsso aalyss: thr coffcts ar tak from th corrlato dagram of th rsdual gas molar calorfc valu at dffrt tmpraturs ad th ar-ful rato, othr thr coffcts from th corrlato dagram of rsdual gas molar calorfc valu rducto dpdg o th ar-ful rato: Q = A t + B t + C D α + E α F, (5) ( ) ( ) mol t + whr Q mol-t rsdual gas molar calorfc valu at tmpratur t ad ar-ful rato α, kj (kmol K) - ; A, B, C, D, E ad F coffcts obtad from th rgrsso quatos. Sc th aalytcal rlatoshp s drvd from th tabl that rprsts oly fossl dsl us, two corrcto factors K ad K ar troducd th modl. Thy tak to cosdrato th ful bld chags th ful hatg valu ad molcular wght compard to dsl ful. Th output paramtrs from th dsl g thrmodyamc calculato modul ar: maxmum ffctv powr N max (kw) at g crakshaft rotatoal frqucy max (m - ) wh th maxmum powr s rachd, ful cosumpto pr hour G T (kg h - ), ad ffctv torqu M (N m) at th sam crakshaft rotatoal frqucy max. If th maxmum ffctv g powr N max ad g crakshaft rotatoal frqucy max at whch ths powr s dvlopd ar kow, th approxmat shap of th g ffctv powr curv ca b dtrmd accordg to th mprcal rlatoshp []: N = N max X max + Y max Z max 3, (6) whr N g ffctv powr at g crakshaft rotatoal frqucy, kw; g crakshaft rotatoal frqucy at th pot to b dtrmd, m - ; 3

5 ENGINEERING FOR RURAL DEVELOPMENT Jlgava, X, Y, Z mprcal coffcts dscrbg th g typ (X + Y Z = ). Emprcal coffct valus for dsl gs from th ltratur data ar: X =.53, Y =.56 ad Z =.9 []. Howvr, usg thm, th atur of th costructd powr curv may dffr from actual dpdg o th g typ, such as turbo chargd or ot, wth drct ful jcto or wth prchambr tc. That s why t s cssary to corrct X, Y ad Z valus. Aalytcal calculato of th coffcts s vry dffcult to rsolv bcaus thr ar two quatos wth thr ukows. O of th mthods s usg stp-by-stp approxmato aalyzg th xstg xprmtal powr curvs [3]. Sc at th Rsarch Laboratory of Altratv Fuls (Latva Uvrsty of Agrcultur, Faculty of Egrg) a lot of dffrt vhcls ar tstd o th chasss dyamomtr Mustag MD-75, ths mthod s usd to fd th coffct X, Y ad Z valus. As a car wth drct jcto ad turbo chargg s adaptd to ru o rapsd ol ful th xprmtal studs [4], cars wth smlar charactrstcs, but dffrt workg volums ar slctd for th aalyss Opl Astra-G.7TD, Mtsubsh Spac Wago.D Turbo, BMW 55 TD, Mrcdz Bz E9D Turbo. Th followg powr curv mprcal coffcts ar obtad from th aalyss ad trd th approprat modl blocks: X =.4, Y =. ad Z =.6. If th valu of th maxmum g powr th full crakshaft rotatoal frqucy rag s kow, th torqu ca b calculatd at ay valu of : M N = (7) Sc th maxmum torqu s achvd at dffrt crakshaft rotatoal frqucy tha th maxmum powr, th addtoal block s placd th modl. Ths block outputs th maxmum torqu valu chckg th formula (7) rsults th full crakshaft rotatoal frqucy rag. Th modl blocks for costructg of dsl g powr ad torqu curvs ar show Fg. 6. Fg. 6. Modl blocks for costructg of dsl g powr ad torqu curvs Rsults ad dscusso At th frst stp of th modl studs th maxmum prctag of rapsd ol th ful bld at dffrt ambt tmpraturs s stmatd, provdg that th ful kmatc vscosty dos ot xcd 5 mm s -. I ordr to mak th smulato asr, svral chags ar mad th frst modul of th modl: ambt tmpratur sldr (Fg. 3) s rplacd by a umbr grator that chags th tmpratur th rag of ºC crmts of ºC; block for cratg th currt bld vscosty curv dpdg o th ambt tmpratur s addd, as wll as MultSm Plottr block that allows graphcal ovrvw of th last four smulato graphs. 33

6 ENGINEERING FOR RURAL DEVELOPMENT Jlgava, Th summary of smulatos s show Fg. 7. v, mm s - 75 RO 5 RO8 RO6 5 RO4 RO DF Crtcal vscosty RO9 RO7 RO5 RO3 RO t, o C Fg. 7. Ful bld vscosty dpdg o ambt tmpratur It s stablshd that to provd ful pump oprato ad th ful flow th ful supply systm wth pur rapsd ol th vhcl ca b opratd up to -4 ºC, wth a bld RO8 up to -7 ºC ad so o. If th ambt tmpratur drops blow -3 ºC, blds wth rapsd ol cott of lss tha 3 % or pur dsl ful ca b usd. I ordr to obta a aalytcal corrlato th frst modul of th modl s chagd aga: rapsd ol cott sldr (Fg. 3) s rplacd by crtcal vscosty of th bld. Th summary of smulatos s show Fg. 8. RO cott ful mx, % y =.33x +.349x R = At crtcal vscosty Blow crtcal vscosty Fg. 8. Maxmum rapsd ol cott th bld dpdg o ambt tmpratur Thus, th corrlato to dtrm th maxmum rapsd cott th ful bld f th tmpratur drops blow -4 ºC s foud. Eg powr ad torqu modllg studs ar carrd out for th sam vhcl that prvously s usd xprmtal studs,.., car VW Golf III.9TD [4]. Th smulato rsults show, that th car g maxmum powr s rachd at 4 m -. Usg dsl ful t s 56.5 kw, usg rapsd ol kw. Th maxmum torqu ths g dvlops at 9 m - : rug o dsl ful 47.9 N m, o rapsd ol 4.3 N m. Maxmum powr ad torqu dffrc 5.5 %. Th powr ad torqu rducto for th car VW Golf III.9TD g s lar ach % of rapsd ol ful bld rducs th maxmum powr ad torqu of aroud.5 %. Comparg th acqurd g powr ad torqu modllg valus wth th data gv by th motor vhcl maufacturr opratg th vhcl wth fossl dsl, dffrcs do ot xcd.3 %. Such cut-off s prmssbl ad dos ot dsturb to dtfy dffrcs opratg motor vhcls wth varous fuls. Coclusos. A orgal mathmatcal modl sutabl to prdct dsl g opratg paramtrs rug thm o rapsd ol ad ts blds wth fossl dsl ful s dvlopd usg ExtdSm softwar. Th rlatoshp that allows calculatg th rsdual gas molar calorfc valu dpdg o th -5 t, o C

7 ENGINEERING FOR RURAL DEVELOPMENT Jlgava, tmpratur ad ar-ful rato s stablshd, as wll as mprcal coffcts for costructg of dsl g ffctv powr ad torqu curvs.. Th modllg rsults show: usg pur rapsd ol vhcls ca b opratd up to -4 ºC, wth a bld RO8 (8 % rapsd ol ad % fossl dsl ful) up to -7 ºC ad so o. If th ambt tmpratur drops blow -3 ºC, blds wth rapsd ol cott of lss tha 3 % or pur dsl ful hav to b usd; rducto of th g powr ad torqu for uadaptd car VW Golf III.9TD g s lar ach % of rapsd ol ful bld rducs th maxmum powr ad torqu of aroud.5 %. Usg pur rapsd ol th dcras s about 5 % comparg wth dsl ful. 3. Comparso of th thortcal ad prvously carrd out xprmtal rsults shows that th thortcal modl ca b usd to dtrm th maxmum rapsd ol cott ful blds at dffrt ambt tmpraturs, as wll as to prdct th g powr ad torqu chags opratg vhcls wth dffrt fuls. Cocdc of thortcal ad xprmtal rsults s hgh. Ackowldgmts Fudg support for ths rsarch s provdd by Europ Socal Fud program Support for doctoral studs LUA, agrmt Nr. 9/8/DP/.../9/IPIA/VIAA/7. Rfrcs. Zhma-Rītņa K. (8) Foslo u augu ļļu masījum dīzļmotorm, to zpēt u ovērtējums (Mxtur of Fossl ad Vgtabl Ol for Dsl Eg, t s rsarch ad Estmato): a Dssrtato for th Sctfc Dgr of th Doctor of Egrg Sccs. Jlgava: LUA, 5 p. (I Latva). Šmgs R. () Bodīzļdgvlas tkm uz motora darba paramtrm (Impact of Bodsl o Workg Paramtrs of th Eg): a Dssrtato for th Sctfc Dgr of th Doctor of Egrg Sccs. Jlgava: LUA, 59 p. (I Latva) 3. Pīrs V. () Botaola zmatošaa ottomotoros (Applcato of Bothaol Otto Egs): a Dssrtato for th Sctfc Dgr of th Doctor of Egrg Sccs. Jlgava: LUA, 9 p. (I Latva) 4. Ful Ols Vscosts (S.a.). [ol] [ctd 3..]. Avalabl: 5. Aza M.N., Kamal A.A.M., Paau F., T W.K. () Vscosty stmato of tracylglycrols ad of som vgtabl ols, basd o thr tracylglycrol composto. Joural of th Amrca chmcal socty, No. 78, pp Estba B., Rba J.R., Baquro G., Rus A., Pu R. () Tmpratur dpdc of dsty ad vscosty of vgtabl ols. Bomass ad Borgy, No. 4, pp Krschbaum S., Rk G. (4) Masurmt of th tmpratur dpdt vscosty of bodsl fuls. Ful, No. 83, p Pulkrabk W.W. (3) Egrg Fudamtals of th Itral Combusto Eg. d d. Uvrsty of Wscos, 46 p. 9. Колчин А.И. Демидов В.П. (8) Расчет автомобильных и тракторных двигателей (Calculato of automobl ad tractor gs). Учебное пособие. 4-е изд. Москва: Высшая школа, 496 с. (I Russa). Itral Combusto Eg Hadbook: Bascs, Compots, Systms ad Prspctvs (4). Ed. by R. va Basshuys ad F. Scäfr. SAE Itratoal, 874 p.. X Q. () Dsl g systm dsg. Woodhad Publshg Lmtd, 88 p.. Pommrs J., Lbrts G. (985) Automobļa torja (Automobl thory). Rīga: Zvagz, 45 lpp. (I Latva) 3. Abolts A., Brjoza D., Prs V. () Thortcal Modl of Explotato of Automobls opratd wth Bothaol-Gasol Mxtur Fuls. I: 9 th Itratoal Sctfc Cofrc Egrg for Rural Dvlopmt : Procdgs, Volum 9, May 7-8,. Jlgava: LUA, pp Dukuls I., Prs V., Jsko Z., Brkavs A., Brzts G. (9) Tstg of Automobl VW Golf Opratg o Thr Dffrt Fuls. I: 8 th Itratoal Sctfc Cofrc Egrg for Rural Dvlopmt : Procdgs, May 8-9, 9. Jlgava: LUA, pp