SHcONGilGHE ?^ 1^ 2< li'''' no NGHIEN CUfU GIAM PHATTHAINO^ BANG PHlTONG PHAP LUAN HOI K H I T H A I (EGR) VASOTDUNG KHfGIAU NIT0(NEA) NO REDUCTION BY EXHAUST GAS RECIRCULATION (EGR) AND NITROGEN ENRICHE[.]
SHcONGilGHE ?^.1^.2< li' no NGHIEN CUfU GIAM PHATTHAINO^ BANG PHlTONG PHAP LUAN H O I K H I T H A I (EGR) V A S O T D U N G KHfGIAU NIT0(NEA) NO REDUCTION BY EXHAUST GAS RECIRCULATION (EGR) AND NITROGEN ENRICHED AIR (NEA) Bui Van Chlnh, Ng uy e n DuTc Khanh d u p c b i e t d e n la m p t b i e n p h i p hCu Tomtit h i e u d e g i a m s U h i n h t h a n h NO^, tren Bai bao trinh bay ket qua nghien cilu giam phat thai NO, tren dgng cO diese! bang hai phiTcfng ph^p d p n g cd d i e s e l Ve n g u y e n tac, t h i i luan hoi khithai (EGR) vasiJi dung hon hup khigiaunito(NEA) Luan hoi thai difocthire hien bang cich sau k h i r a k h d i d p n g c o d u p c t r i c h mflt trich mpt phan thSi sau kh6i dong cO dija trd lai dutmg nap, phia trudc may nen nhd chenh p h a n t r d lai d U d n g n a p v a hda trpn ap T} le luan hoi duoc dieu ehinh bang cich thay doi mci cia van EGR Khi giau ni to (NEA-Nltrogen v d i k h i n a p t r U d c k h i v a o d d n g cO Khi Enriched Air) duoe eung cap vao dgng co bing each bo tri mgt voi phun ni to tren dudng nap, phia sau l u i n h o i b a o g d m chCi y e u x i t c i c bor ket lam mat khitang ap trudc vao dgng co Lifu lUong ni to phun vao difdng nap dirge dieu chinh de (COj), n i t d ( N j ) va h d i n U d e se dupcdua cd the dat difflc ty le khoi lifong da ni to khong nap Idn hffn 77 % Ket qua nghien eiiu cho thay, t r d i a i x y l a n h d e l a m l o i n g h o n hop sfidung giiu ni to c6 kha nang giSm thieu phat thai doc hai NO^ tuong dUOng vdi phucmg phap EGR e h a y v a g i i m n o n g d o o x y t r o n g bu6n5 dd cong suat ciia dfing ca diTOc cai thien vcfi ty le NEA phii hop, phat thai CO giam va phat th^i c h i y N g o i i ra, n h i e t d u n g r i e n g cOa kh dang hat thay doi khdng dang ke l u a n h o i I d n h o n r a t n h i e u so v d i khonc Tir khda: phat thcii ddng co diesel, giim thieu NO,, luan hoi khithai EGR, NEA k h i n a p n e n k h i l u a n h o i l a m t a n g nhi& d u n g r i § n g eCia k h i n a p , d o d o se ISn Abstract g i i m d p t i n g n h i e t 6o t r o n g d p n g ct This paper presents the study results of NO, reduction on diesel engine by mean of providing nitrogen v d i cLing l U p n g n h i e t g i i i p h d n g cCii enriched air (NEA) to engine and using exhaust gas recirculation (EGR) method EGR was conducted by q u a t r i n h c h i y t r o n g b u o n g ehay Hlnl introducing an amount of exhaust gas from the engine into intake manifold before the compressor thank t h e h i e n s o d o h e t h d n g l u i n h6i kh to the pressure difference between exhaust gas and intake air The EGR ratio was adjusted by EGR valve, thii which placed on recirculation pipe, NEA provided to the engine by a nitrogen injector which is placed on intake manifold after the tntercooler The mass flow of nitrogen injected to intake air was controlled to archive proportion of nitrogen in intake air greater than 77% by mass The results show that NEA could decrease NO, emission as well as EGR method; CO emission was decreased and Soot emission was constant while as the brake power of the ICE improved slightly Keywords: diesel emission, NO, reduction, EGR, NEA Hinh So he thong luan hdi khithai EG"' TtiS BUI Van Cliinti, Khoa Cong ngtie to, Tmdng Oai hoc Cong nghiep Ha Ndi KS Nguyen Bdc Khanti Vien Ca Dong lircTn/dng Dai hoc Bach khoa Ha Noi Email khanh.nguyenduc@hii5Ledu Ngiy nhan bai: 13/08/2013 Ngiy chap nhan «ang: 07/10/2013 Luan hdi t h i i mot bien phi kinh te g i i m thieu p h i t thai NOj,, tL nhien cd nhieu han che nhu lam tar ham lupng p h i t t h i i dang hat (PM) \ GlOlTHlIU CHUNG ket q u i cua sU dU thCfa ham lUpng Phat t h i i d xit ni to (NO^) la mpt dxy va nhiet dp q u i trinh chay eao E>a nhang t h i n h phan p h i t t h i i doe ed nhieu cong nghe giam NO^ dupc hai chfnh eua dpng co diesel, d i e biet nghien cufu va p h i t trien L u i n hdi tren dPng cd diesel tang ap bdi nd la thai (EGR - Exhaust Gas Recirculation) TapdiiKHOAHOC&CONGNGHl* So khdi den, d i e biet la d che dp t i i Idn"^ lam g i i m chat lupng dau boi trdn'"' nhieu k h i n i n g gay m i i mdn pisto xylanh, g i i m ben cua dpng cd '*", Ngoai bien p h i p l u i n hdi th CO mpt s6 g i i i p h i p da dupe nghii SClENCETECHNOLOGYl Lfu khdng nhCfng giam thieu NO^ ma dn khic phuc dupe nhUng nhupc lem ton tai eua phUdng phap nay, ae nghien eijfu cho thay ham lupng xy nap la yeu td anh hudng Sn nhat tdi hinh phat t h i i NO^ rong dpng cd'^""' Anh hudng cua ham lupng oxy lay ham IUdng ni to) nap len nhiet dp doan nhiet cua ngpn lifa la duoe thCf nghiem bdi Olikara v i lorman"" Hinh the hien quan he ihiet 66 doan nhi^t vdi h i m lupng ni buong chay Dd thj cho thay ihiet dp g i i m ham IUdng ni to rong nap tang len d cCing mPt t^ s A/F Khi ham luong oxy g i i m tCf % :u6ng 17% v^ the tich hay ham lupng li td tang tif 79% den 83% thi nhiet dp / thuyet cua ngon ICfa g i i m khoing :50"K Nghien cdu g i i m lUpng dxy hay ang lUdng ni t d nap de g i i m ihi§t dp q u i trinh ehay se lam giam uong NOj hlnh buong :hay Bang So sanh hai phuang phap EGR va NEA Luan Cang cap fdiigiau niUtNEA Khi nap ban hon cac chat thai dang hat Khdng anh hifdng tdi tudi tho hay ben dia thai luan hdi ddng CO, TUOI tho vh dd ben cua ddng eo gi^m anh hUdng ctia Nhiet dd nap thap, tang dUOc lUOng mdi axit luan hdi chat nap Khi luan hoi ed nhiet cao se giam he sd nap Hon hop ddng nhat, ddng co lam viec on dinh {)6ng CO lam viec kem on dinh; dao ddng giifa eae chu hon ky Idn, Can cd thiet bi tach khdng dac biet lap tren Can bd tri ket lam mat luan hoi, van dieu chinh ty le dudng nap, gay ton that ve luu luong va ap luar hdi va bd loe chat thSi dang hat va hop chat cua suat o n g 16 cP t h e h o a t d p n g d p lifu huynh chenh lech i p suit kha nhd v i co k h i nang tao ty le Idn hon cic phUdng p h i p tao n i t d khic Hlnh Ddng CO diesel tang ap trang bi bd tao NEA Hinh Quan he giCa nhiet ngon li^a va ndng Viec cung cap nap vdt ham U d n g o x y t h a p , h a y c d n g p i la k h i g i i u li t o N E A ( N i t r o g e n E n r i c h e d A i r ) c o t h e hay t h e d u p e bien phap truyen t h o n g ;GR vdi n h i e u han che, Dudi day l i m p t d so s i n h Uu n h u o e d i e m e u a p h u o n g ) h a p SLf d u n g k h i g i i u n i t d NEA so v d i )hUdng Khi k h P n g k h i c d a p s u i t cao di q u a d n g , sU c h e n h l e c h a p s u i t b e n t r o n g '6 ni ttf"! phap luan hoi thai EGR bingi) Cd nhieu nghien cufu tao NEA de :ung c i p eho dpng cd, dd dien llnh la nghien ciJu cua Nemser v i cpng u"^i Nguyen ly hoat ddng co b i n va ;et cau cua mang tach dupe the lien tren hinh Mang tach dang hoikhithiiKR Khi nap sach, khdng ed cac chat dang hat va ben ngoii ong l i m cho mpt phan dxy duoc Uu tien di qua dng (be mat ben ngoai t h i n h dng l i Idp perfluoropolymer) ngoai mdi trUdng cdn ni to bi chin lai va di ehuyen doc theo ong den dau cua thiet bj Dau cua thiet bj l i khdng dupe lam giau ni td Bp tao NEA cd the lap true tiep tren dUdng nap de cung cap kht cho dpng cd thed cie ehe 66 lam viec Hlnh the hien sd nguyen ly dpng cd diesel tang i p bang tua bin t h i i cd trang bj thiet bi tao giau ni to Khi t i n g ap khdi m i y nen se dupe lam m i t qua ket l i m m i t trung gian trudc di qua thiet bi tao NEA Ap suat eCia tang i p sau ket lam m i t quyet dinh den ty le ni t d trudc di vao dong cd Oe iam ro hdn Uu viet eCia phUdng p h i p sis dung NEA nham g i i m thieu NOjj tren dpng cO diesel tang i p , nghien cufu nay, mo hinh tinh t o i n chieu giam thieu p h i t t h i i NO^ cua ddng eo diesel t i n g i p bang hai phuong p h i p EGR va NEA dUpc thUe hien de so sanh Md hinh tinh toan dUdc xay dung tren phan mem md phdng chieu AVL Boost Phan mem cho phep tinh toan mP phdng dUpc chu trinh lam viee cCia dpng cd cung nhu tinh toan dupc cic t h i n h phan phat t h i i dpc hai Ket q u i nghien eijfu danh g i i dUpc anh hudng eua hai phuong phap tdi cac thdng sd ky t h u i t va phat thai dpc hai cCia dpng co, nhat la phat thai NO^ va Soot N Q I D U N G N G H I D N CLTU 2.1 Xay dUng mo hinh mo phdng Doi tupng nghien cdu la dong ed i-M> Hinh 5, Md hinh chieu ddng co 01146Ti So 18.2013-Tapchi'KHOAHOC&CONGNGHE EEniEHCpNGNGHL diesel D1146Ti, t i n g i p bang tua bin may nen, lap tren xe bus Cac thdng sd ed ban cua dpng co the hien bing DUa tren cac thdng so ky thuat cLia n h i san xuit cung nhU eic thdng so dac tren dong cd thUc te Mo hinh chieu cua dpng cd Dl 146Ti dupe xay dung tren AVL Boost nhU the hien tren hinh Hlnh the hien md hinh dong ed trang bi he thdng luan hoi t h i i ap suit thap Khi thai sau khdi dpng cd dupe trich mpt phan trudc tua bin de dua qua ket lam mat trung gian trd lai dudng nap, sau trpn vdi khdng trudc duoc hut v i o miy nen ia a(%) - he s6 ty le - Trudng hpp luan hoi thai, a dupe x i c dinh nhu sau: a = :]!}§GixiOO% = -^^^x100% nikfc ^xlOO% = Bang Cac thong sd eo ban cua ddng co TT Thong so Ten S6xylanh(-) Kieu (-) DxS (mm) Cong suat dmh mJc/t6cd6[kW/v/ph) Mo men I6n nhat/toc So [Nm/v/ph) Tysonen fionvi 111x139 154/2200 880/1600 16,8 2.2 Md hinh chay IVlo hlnh tinh toan p h i t thai dpc hai cOa ddng ed sLf dung nghien cdu l i mP hinh AVL MCC f>/16 hinh MCC cd the dU doin dUpc tdc tda nhi&t v i tinh t o i n dUde cic t h i n h phan p h i t t h i i dpc hai chinh cua dpng cd diesel nhU NO^, bd hdng (Soot) va mond xit cicbon (CO) Mo hinh yeu cau cic thong sd ket cau va thdng sd lam viee nhu sd 16 kim phun, dudng kinh 16 phun va ap suat phun 2.3 Quy trinh thuc hien Nghien ciJu dupe thuc hien theo quytrinhsauday: - Xay dung mo hinh dong ed D1146Ti nguyen b i n , tien hanh danh g i i chinh xac bang cich so sanh mdt sd ket q u i tinh toan mo phdng vdi ket qua dac va tien hanh nhCfng hieu chinh de md hinh dat 6nac dp tin cay can thiet, - Tien hanh dieu chinh lai ket ciu dudng nap, t h i i cCia ddng cd sau kiem nghiem de co dupc hai mo hlnh g i i m p h i t t h i i nhu the hif n tren hlnh v i hlnh -x100% K^T QUA M Q P H N G VA THAO D1146TI Chay nen f^MP; Vdi m^^f, ^ m^p, la IUdng thai l u i n hdi (g/s); m^^^ m^p^ l i tdng lupng mdi chat nap (g/s) -TrUdng hdp sCf dung giau ni to, a 6\jac xac djnh nhu sau: LUAN 3.1 Danh gia mo hinh Dp tin cay eua mo hinh dupc danh g i i bang each so sinh ket qua mo Hlnh 6, (lAd hinh ddng cO trang bi luan hoi phdng va t h i nghiem cdng suat co ich d cic dudng dac tinh tde dd eija dong cd nguyen ban nhUthe hien tr§n Hlnh Ket q u i mo phdng thu dUOc cong suit cd g i i tri sai lech Idn nhat -4,9% tai toe dp 2200 v/ph, 50% t i i va sai lech trung binh -0,2% tr§n toan dai toe dd cua dpng ed K^t q u i kiem nghiem mo hlnh chiy dUpc the hien qua cic thj so sanh cic phan phit thii doc hai cua dong co (NO^, Soot va CO) giCfa mP phPng v i thi nghiem tai che Hlnh Mo hinh ddng eo cd vol phun ni to 75% t i i , tdc 1600 va 2200 v/ph (tiS Hinh the hien mP hinh dpng cd sCf hinh 10 den hinh 12) Nhin chung, giiJa dung bien phap g i i m NO^ bang each ket qua mo phong va thi nghiem co SLf SLf dung NEA De ddn gian, NEA sai lech nam gidi han cho ph^p duoc tao b i n g each bo tri vdi phun Sai lech ldn nhat la 8,5% ddi vdi phat ni to (I - Injector) vao dudng nap de t h i i CO tdc dp 2200 v/ph NhU vay co hda trpn vdi khdng trUde di vao the sd dung mP hinh de thuc hi&n ddng CO eic tinh t o i n nghien cijfu khic tr§r -Tien hanh md phong q u i trinh lam dpng CO viec cua dpng co trang bj he thong EGR va NEA d che dp tdc 1600 va 2200 v/ph, 75% tai LUpng luin hdi dupc dieu chinh nhd thay doi dp md cua phan tCf c i n (R, tren hinh 6) de dat dupc cic ty le luin hoi khac Lupng ni to phun vao dudng nap dupc dieu chinh d cic luu lUpng khic de chiem cho mpt phan nap Thdng sd chung de danh gia ty le EGR hay ty le ni to phun vao dudng nap 38|TapdiiKH0AHpC&C0NGNGHE So Hinh 9.Congsuatvasuattieu hao nhien li^ugiii md phdng va thifc nghiem SClENCETECHNOLOGYl HlnhlO So sanh phat thai NO^ Hlnh 14 Dien bien nhiet dd Idn nhat budng chay theo ty leo Hlnh 11 So sanh phat thai Soot Hlnli 16, Phat thai CO theo tf leo a) 1600 vdng/phijt;b} 2200 vdng/phut tiep tue t i n g t^ le a, cPng suat bi g i i m xudng ni td nhU la mpt tro l i m tang nhiet dung rieng cCia mPi chat (khoing Vi so vpi CO^), ddng thdi luong Pxy giam manh lam thay doi cau true cua ngon ICfa chiy va thdi gian ehay Sy thay doi nhiet dung rieng cua moi Hinh 12 So sanh phat th^i CO chat cung nhu sU suy g i i m ham lupng 3.2 Anh hiiitng tdi cong suat va dxy lam g i i m nhiet dp chiy nhu the Hinh IS Phat thai NO^ theo ty lea hat thdi tfdc hai cCia dpng ccf hidn tren Hinh 14 Khitang a den 17% a) 1600 vdng/phut; b) 2200 vdng/phut thi nhiet dp cue dai buong chiy giim ISO^K ddi vdi EGR v i 320°K ddi Hinh 13 the hi^n dien bien edng vdi NEA d hai tdc dp 1600 v i 2200 v/ suat CO ieh cua dpng cO theo ty le ty le ph Dieu khdng nhufng i n h hudng d che tde dp 1600 {hlnh13-a) v i tdi cdng suat eua dong eo m i cdn i n h 2200 v/ph (hlnhl 3-b), 75% t i i Ket q u i hudng manh tdi dien bien cic t h i n h cho thay, thUc hien luan hdi t h i i phan p h i t t h i i dpc hai, die biet l i p h i t thi cdng suat eua dpng cO g i i m xudng, t h i i NO^, ma nhiet dp chay l i yeu to cang t i n g ty le a eong suit cing giam chinh hlnh phat t h i i dpc hai niy Nguyen n h i n la c h i t lupng q u i Hinh 15 the hien dien bien cua phat trinh chiy kem di vi thieu oxy cung t h i i NO^ theo ty le a Ket q u i cho thay nhu nhiet dP chiy g i i m xuong bdi c i hai phUdng p h i p deu cd k h i n i n g phan COj va ni t o t h i i g i i m thieu NO^, tUdng dUdng lam t i n g nhiet dung rieng cua mdi vdi tv- I& a3^ on Soot Formation in a High-Speed Direct-lnjecHfli thai Soot theo t^ le a Do thi cho thay , ID » ft/ 22IKIrpni - 11 J t , 3-' 1" ^ Kreso, A.M„ J,HJohnson, LD,GraH of Exhaust Gas Recirculation on Heavy-Duty Diesd vdi phUdng p h i p EGR Engine Emissions," SAE Paper 981422,1998 [4] Leet, J.A, A.Matheaus, and D,Diclffij, le a tdi 17% p h i t t h i i Soot tang 158% "EGR's Effect on Oil Degradation and Intalce System va 116%dtdc dp 1600 v/ph va 2200 V/ Performante/'SAE Paper 980179,1998 ph SU khic biet la nap sach [5] Dennis, A,J., CRGarner, and D.H.C,Taylor, va ddng deu hdn sCf dung NEA, eon "The Effect of EGR on Diesel Engine Wear," SAE Papei chat t h i i dang hat chda t h i i lam tang k h i nang hinh phat thai Soot Hinh 17,Phat thai Soot theo ty leo KET L U A N a] 1600 vdng/phiit; b) 2200 vdng/phut Nghien cLfu giam p h i t Pxy nhu d i p h i n tich d tren [3] S.T.Bagley, and D.CLeddy, "A Study of the Effect hudng tdi hinh phat t h i i Soot, SLf dung EGR nap ban hdn cac nhiet dp qua trinh chay va ham lUdng Diesel Engine,"SAE Paper 960841,1996, SLf dung NEA gan nhU khdng gay i n h phat t h i i Soot tang manh Cu the vdi ty [t^ 12] Ladommatos N., R.Balian, R.Horrocks, and LCooper, T h e Effect of Exhaust Gas RecirculaBmi sddung NEA Hinh 17 the hien di§n bien eua p h i t o; Review, 2005 tuong u'ng d tdc dp 1600 v i 2200 v/ph 1999-01-0839,1999 [6] Nagai, T,, H.Endo, H.Nakamura, and H.Vano, "Soot and Valve Train Wear In Passenger Car Diesel Engine,"SAE Paper 831757,1983 [7] Nagaki, H., and K,Korematsu,"EffedofSuii t h i i NO^, Dioxide in Recirculated Exhaust Gas on Wear withfii bang hai phuong p h i p luan hoi t h i i Diesel Engines,"JSME Int'l J., Series B, Vol 38, NaJ, EGR va SLf dung giau ni t o NEA dupe pp 465-474,1995 So vdi phat t h i i NO^^, i n h hudng thUc hien b i n g edng eu md phdng [8] Plee, S.L, lAhmad, and J.PMyers, "Flame cOa ty le a tdi p h i t t h i i CO va Soot thi chieu Cac ket q u i nghien edu cd the Temperature Correlation for the Effects of Exhausi ed xu hudng ngUdc lai Hinh 16 eho duoc tdm t i t nhu sau: Gas Recirculation on Diesel Particulate and NO) thay dien bien cCia p h i t thai CO theo t^ - SCf dung NEA ed the eai thien dUpe \k a Vdi phuong p h i p EGR, tang ty cdng suat cua dpng co vdi ty" l§ ni t d [9] Rdpke, 5., G.W,Schweimer, and TS,Strauss, le a, phat t h i i CO tang len phu hdp, sd dyng EGR "NOx Formation in Diesel Engines for Various Fuel! sd dung NEA lai g i i m thieu dUdc p h i t cdng sua't ddng cd giam and lntakeGases;'SAEPaper950213,1995 t h i i CO Cd the g i i i thich hien tupng nhU sau: sCf dung EGR ngoai i n h hudng chiem chd nap, l u i n - Khi nang g i i m thieu p h i t t h i i NO^ tdi CO t i n g , Trong vPi phuong phap NEA, lupng ni t o phun v i o dUPng ^ [10]Lapuerta,M,,JIVI.alavert,andCDomil^ cua hai phUdng p h i p la tUdng dUdng "Modeling and Experimental Study about the Effeci vdi tylea3^ on Soot Formation in a High-Speed Direct-lnjecHfli thai Soot theo t^ le a Do thi cho thay , ID » ft/ 22IKIrpni - 11 J ... lUpng dxy hay ang lUdng ni t d nap de g i i m ihi§t dp q u i trinh ehay se lam giam uong NOj hlnh buong :hay Bang So sanh hai phuang phap EGR va NEA Luan Cang cap fdiigiau niUtNEA Khi nap ban hon... Idp perfluoropolymer) ngoai mdi trUdng cdn ni to bi chin lai va di ehuyen doc theo ong den dau cua thiet bj Dau cua thiet bj l i khdng dupe lam giau ni td Bp tao NEA cd the lap true tiep tren