Mô phỏng hệ thống phun trực tiếp nhiên liệu khí thiên nhiên nén trong động cơ đốt trong đánh lửa cưỡng bức

Tuyen tap Cdng trinh Hdi nghi Khoa hoc Cff hoc Thiiy khi Todn qudc, Phan Thiet, 2008 377 Md phong he thong phun trirc tiep nhien lieu khi thien nhien nen trong dong ca dot trong danh liia cu ong birc[.]

Tuyen tap Cdng trinh Hdi nghi Khoa hoc Cff hoc Thiiy Todn qudc, Phan Thiet, 2008 377 Md phong he thong phun trirc tiep nhien lieu thien nhien nen dong ca dot danh liia cu-ong birc Le Van Tuy, Phan Minh Due Trudng Dgi hoc Bdch khoa-Dgi hoc Dd Niing Tdm tdt: Khi thiin nhiin nen (CNG) Id mdt nhirng nhien lic'u thay thi tricn vgng cho vdn di gidm thieu d nhiim mdi trudng vd da dgng hda nguon nhiin lieu, lie thdng phun CNG true tiip cho phep ndng cao ty so nin dgng ca vd td chirc qud trinh chdy phdn lap de ndng cao hiiu sudt cdng sudt ddng ca vd tiet klim nhiin lliu Bdo cdo trinh hay phuang phdp md phdng mdt hi thdng cung cdp CNG bdng phirang phdp phun true tiip vdo xy lanh ddng ca dugc diiu khiin bdi van thuy diin tir Kit qud nghiin ciru cho thdy diin biin cdc thdng sd dgng lire hge thuy cua CNG hi thdng phun true dip: qua cho phip phdn tich dnh huirng cdc thdng sd kit cdu cimg nhu van hdnh din chdt lugng phun nhdm tdi uu hi thdng phun Khdc vdi hi thdng phun nhiin lieu long truyin thdng, md hinh \di hi thdng phun true dip CNG kiiu vdi phun mgt Id, dudng kinh Id phun Idn vd dp sudt phun thdp (4,4 din 8,4 MPa) vdn bdo dam chdt lugng cdp nhiin liiu td chirc chdy vin hda phdn lap A Simulation of CNG Direct Injection System for Spark Ignition Engine Abstract: Compressed natural gas (CNG) is one of alternative fuel to reduce exhaust gas emission and diversify fuel for internal combustion engine CNG direct Infection provides ability of increase of compression ratio, therefore engine power and fuel economy This paper presents simulation of a CNG direct infection system with electro-hydraulic injector for spark Ignition engine Dynamic of the CNG In the system with varied system geometry and operational condition was analyzed and optimized The results revealed a reversed trend compared to injection system for conventional liquid fuel: stratified charge could be achieved even with a large diameter single-hole injector, low Infection pressure (about 4.4 to 8,4 MPa) Keyword: Natural Gas, Spark Ignition Engine, Direct Injection, Stratified Charge Gioi thieu : Trude tinh hinh can kiet cua dau md va ap lyc ciia luat bao ve mdi trudng ddi vdi bau quyen, ngoai cac giai phap hoan thien ddng co nhiim tiet kiem nhien lieu, ban che cac chit thai ddc hai dgng co ddt gay ra, viec tim kiem cac ngudn nhien lieu mdi thay the, la myc tieu hudng tdi ciia phan Idn cac nghien cuu phat trien hien tren the gidi; va dd cung la muc tieu hudng tdi cua dc tai Trong cac loai nhien lieu mdi sach, thi nhien lieu thien nhien nen CNG {Compressed Natural Gas) dugc cac nha khoa hoc quan tam hang diu vi day la ngudn nhien lieu sach va day trien vong cho old sinh thai tuang lai [I, 8] Nhien lieu CNG dugc menh danh la nhien lieu eye sach nhd phan carbon chua h-ong nhien lieu la thip nhit tat ca cac nhien lieu hydrocarbon CNG la ngudn nhien lieu triln vgng vi chung phan bd . nhôiliiu*WI>li>)M*ằl>l'ôn*JnằcôDlwl-(llthtohằlMmôn^liằpCWaa n -ã.''C'l iM- t>u i#(X I " i v i bwadV l u ^ aio v^i, »oi iikuu' [ Tlr^t.^ %f 1-3 ii: ••••-1 vp p'uj, i- tfr^ w | l"^ (••*(• 1C'(^ ' *;•• JPr^-J.^r, l»! j ^-jsm i I • ' i • _^ I ' j I i i j ! ; ' i /-• •j - ^-, \, •1 - ' • j I •.^'1 CKJU) uiui,' uio,"- ;i'.tii' ujj'O '.'U-ij Hu)* uu/i.' 'I'ty-i b,ir u/iA a^'t tU^n 0i(ini^ qua c^k- v«n Mb/>Aun 5.' [mm"}] Hinh H3.1 : Dien hien cdc ddc tinh dong-ma cac van vol phun > M a M n ailii uirdi^V fitiitn k w kM Itirin nhiin M n « n g sa OiM*l • [Mb M l h phun i n c b

i : r i ! i i J i n mfii i c n u^-u i t i i r t i J t i fc) O i m iN.r/1 luu itAJnf, 4fi4U cik: »vin »dtf ^-jAtwr ^) /.yn-'-^.j/ mm-M?:^ Hinh H3.2 : Diin biin cdc dgc tinh lim luang vd dp sudt Le Vdn Tuv Phan Minh Dire »ltohitocUU»^Jun»iii*»t«»n« pAiin v /m'j) P'^v-y um^tj- ///«/z / / i , i Diin biin mot sd thdng sd ddng hoc nhien lieu qua vdi phun Cac ylu to anh hudng din chit lugng phun : Lugng phun chu trinh phu thugc bac hai theo ap suit phun pf, dudng kinh lo phun {vd ty sd duang kinh Id phun) nhung chi phy thudc bac nhit theo thdi gian phun Xk[mm] minj [mg/inj] 0.350 35 -r 0.300 30 11,186.|),2-64,1)75,p, + 82,131 0.250 25 0.200 20 0.150 15 0.100 10 — 0.050 0.000 3.9 4.0 4.1 4.2 4,3 4.4 4,5 4.6 4.7 4.8 4.9 ap suit phun Pf [MPa] Hinh 4.1 : Diin biin luang phun chu trinh thay ddi dp sudt phun Md phdng he thdng phun true tiep nhien lieu thien nhiin nen ddns ca ddnh lira cuonis birc 386 nirj Img/inj] 0,300 ^ 0.250 m,n, = 1,0375.[)p'- 11.£05 Dp-;.9.628 0.200 0.150 tn, : 0,0838 Dp- 1,2:22 0.100 0.050 15.6 15,5 15.7 15.8 15,9 16.0 16.1 16.2 16.3 0,000 16.5 16,4 Difang kinh piston 6ieu khiSn kim phun Dp Imm] Hinh : Dien biin luang phun chu trinh thay ddi du&ng kinh phun vfk.^^\rl if « ui-l J- I M I iJ o-B ^ -.liJiT i m J.- C4:ii:X> i;i.4ljii:i: ».iJ.»a.-U a - - ' ' " i I ~ r ^ Pitfl t i f f ar 1 ? tol l i m * i » i r i j ( » ' 1 if- • I i I ' — • • • 1 : \ \ Jl ;.— ;i il ; i Jl : '1 '• • 1J i;)ii oôt: iiô Oijm; i : / < ôãô: II-JT ôã*ô: I U ằ J .l U.V iU' A/V LlA '/ D i ^ ij*r.T J t ' A A S (ifi( A.'-ii't, J;' M^i/ ;.'\itir P ^'U » fu ^ / * ) j ; ,/.^,^, -^vi-, j-ii T -iôrr tiT tj-^ir^i ã ,i4f.l,LLr,Q[,^n'i\! Hinh 4.4 : Su biin ddi ndng kim phun, tiit tie! thdng qua theo mirc triing diep cua van cdp xd Toi ITU hoa he thong phun true tiep CNG voi kieu van dien tii kep : Ket qua nghien ciru va phan tich anh hudng cac thdng sd ket cau va van hanh den chat lugng phun da ehi giai phap mdt nang cao chat lugng phun la dimg van dieu khien dien tir kep se giam thdi gian qua cua giai doan ket thuc phun, tao sy tap trung tdt ban cho giai phap td chirc hda phan ldp Hinh 5.1 : Ddc tinh dieu khiin ciia van dien tir kep (xi ddc tinh md/ddng van xd, x, ddc tinh ddng/m& van cdp) Md phdng he thdng phun true tiep nhiin lieu thiin nhiin nen ddns caddnh lira cuong birc 388 mTTr^7; r_^';^' "ii," •' !•' TTtl 'i:i' l',^I' J l.Ti'.r.-'-J•:i.:ESM < •"'-' j t ' " " „ i ; - t r ' ! ' '• - • i - i • -y; i • - • — u.^ — '- _ i - i,'i -A : , """" •-•'': y - ^ •f J/< iuu> •iu'ii »IM'^ , iV' a fe^-'gfe- •>i:23fe^ iizi: L'TT-T"'' ////l/l H5.2 : Diin biin dp sudt, vd luu luang qua cdc van LUJ V' I •" b i' f; n ,1, ,ằ;ô.ô,,.i ã ã ' '• t - r • i ^"'L1-LT ///Ai/i //5.i ,• Phdn hd ndng tia phun nhiin lieu xy lanh ([%J hoac [-]) H'i,T,r,Ti?rt~TnTi IMt-TJ / •r-l "-^i" : |,K: .—, i j - , • • > O I -,_ ^ I — - J T fe/r^.^g^'^T'S^'^^^v ] ; I i L 7rKr.T:i,-5-j«I*7- ,-TBiaiaBflii!iJiBt»Miai'"?c>:g~i;g5gaai Hinh H5.4 : Qui lugt phdn hd ndng dd tia phun theo phir&ng hu&ng tnic & hu&ng kinh Li Vdn Tuv, Phan Minh Dire 389 ac3ssxsnn2EZ •' Tn^fi nfrj fO"! — r [-'"- - -'"i — - ' r i~ ' • — 4- - i- i i P2J • - I — — , _ L_ _, u _ - , ^- — J 1 — 1 ; t~"i ~ — _ :_ i_ - ^^ H-l '.» - " • ' r FT ^ - - • .- _:• i1 _ i : .J; _ fez,rr>^F^g=^-^t^'^P°^'^=^^B^ If ^'M •1 ittf l— ' -.-1i —:J, iLr ^:: ^ , 1 , f' ' ' j ,» ,.», ;- •1 •-c,U- —•" - - _- !. « L,L - T J - t I:-I- M» ' ^ i i—t — i- ~T 11.-• "" I TTKt ! _ » '"•"^^-J^^'-^-^f^ffifsngrama'^-fT-^f^ //!/7/i //5,5 ,• Qui lugt phdt triin tia phun (kem theo ndng dd) theo ihdi gian phun Ket luan : Xay dyng duac mgt md hinh he thdng phun trye tiep nhien lieu klii CNG dgc lap, dan, dieu khien bdi van dien tir kep, ap suat phun trung binh (tir 4,4 MPa irng vdi ty sd nen 12:1 den 8,4 Mpa irng vdi ty sd nen 17 :1) Md hinh thiet lap hoan loan dap img va phii hgp vdi md hinh thyc nghiem brong duong cd kieu vdi phun don (mgt Id), dudng kinh Id phun Idn Df = 7,25 [mm], ap suat phun khdng cao pt = 4,41 [MPa] cho dgng ca CNG cd ty sd nen trung binh £ = 12 :1 [16] vdi luang phun nhien lieu CNG cho chu trinh m.^j = 17,262 [mg/inj] Thdng qua phan mem lam cdng cu phan tich, cho phep phan tich danh gia tdt cac thdng sd ket cau cung nliu van hanh (ca he thdng phun va dgng co) den chat lugng phun ; qua dd cho phep dinh hudng, dy bao tinh tdi uu ddi vdi he thdng phun trye tiep nhien lieu CNG cho dgng co dot ndi chung va dgng co diesel ndi rieng Lugng phun hoan toan phu thugc tuyen tinh vdi thdi gian phun Tao thuan Igi cho ky thuat phun hai giai doan : phun sdm ddng nhat loang va phun mugn phan ldp phu thugc vao chl tai van hanh cua dgng co {md hinh phun hai giai doan d 100% duac minh hoa & cdc hinh H6.1 vd H6.2) Nbicn lieu thicn nhien nen (CNG) ciing vdi cac nhien lieu sach thay the khac la giai phap diy triln vgng cho van d l giam thilu d nhicm mdi trudng trude tinh hinh dau md dang can kiet doi vdi hiu hit cac qudc gia tren thi gidi hien Nghien cuu khai thac va sir dung hieu qua nhien lieu thien nhien cho dgng co dot khdng nhiing cho phep lam giam ap lyc phu thudc vao nhien lieu diu md dang khan hicm va sap can kiet ma cdn lam da dang hda ngudn nhien lieu cho ITnh vyc giao thdng van tai ndi roieng va dung cho dgng ca ddt ndi chung Tuy nhien ngudn nang lugng thicn nhien ciing cd ban, vi vay ben canh nhiing giai phap cong nghe nhiin khai thac sir dung hicu qua va tilt kiem nhien lieu CNG cho dong ca dot ; cung can cd nhirng giai phap tdng thi, ddng bg dl su dung hieu qua va tiet kiem ban nguon nhien lieu sach cho giao thdng van tai Md phdng he thdng phun true tiip nhien lieu thiin nhiin nen ddns ca ddnh lua cuans buc 390 fr [%] 100 - / 90 - / 1/ 80 70 - / 60 - / 50 40 30 - i / ' / 20 - / / 10 -