Overvie view w & Perspecti spectives es for Inter ernal al Combustion mbustion Eng ngine ine us using ng STAR AR-CD CD Marc ZELLA LAT
TOPICS PICS Quick ck overvie iew w of ECF CFM M fa famil ily y models ls Examples xamples of validat dation ion for Diesel and d SI-GDI GDI engines ines Intr trod oduc ucti tion on to multi ti-com componen onent t fuels Applicati ication on and d validat dation on of multi ti-comp component onent fuel to SI-GDI GDI and d Dual al fuel engines ines – Real multi-component gasoline – Influence of anti-knock additive in the fuel mixture – Dual fuel : Diesel/Natural gas combustion Conclus clusion on and d perspectiv ectives es G. Desoutter, A. Desportes, J. Hira, D. Abouri, M. Zellat
A General ral Schemati ematic c View of Spray y and Combust mbustio ion n Mixtur ure e fluctuations uations • Diffusion reaction zone • mixture • Air • c Auto-Igni Ignitio ion Temperat eratur ure e fluctuations uations • Z Post-ox oxidat idation ion st Kinet etic ic controll rolled ed • Large scales : τ=k/ε Mixtur ure e fluctuations uations (integral lenght ) Temperat eratur ure e fluctuat uations ions • Small scales : τ=(ν/ε)** 0.5 (Kolmogorov lenght) • Demoulin & Borghi, Comb.Flame,129(2002)
THOE OERETICA RETICAL L ECFM-CLEH CLEH MODEL EL DESCR SCRIP IPTION TION: : ECFM FM-3Z 3Z / ECFM FM-CLEH LEH models els : : conceptu ptual al frame mewor ork spray ‘EXTENDED COHERENT FLAME - 3 3 ZONE’ fuel possible fluid states in computational cell fuel injection into charge (air + egr) air + egr spray fuel mixing of fuel and charge mixed air + egr spray time fuel ignition in mixed zone mixed air + egr spray fuel burnt Combustion in mixed zone unburnt + Un-mixed in burnt gases mixed air + egr G. Desoutter, A. Desportes, J. Hira, D. Abouri, M. Zellat
THOE OERETICA RETICAL L ECFM-CLEH CLEH MODEL EL DESCR SCRIPTION IPTION: : pt : Flame lame str tructure cture ECFM FM-3Z 3Z / ECFM FM-CLEH LEH concept ECFM-3Z 3Z ECFM-CL CLEH EH Spray Zf/unmixed Zf/premixed Zf/diffusion Transfer fer is function tion of c only The diffus usion on zone ne is unmixed ixed burnt nt gases es Transfer fert if Phi > Phi.cr i.crit it. The post-ox oxidat idation ion is mixed ed burnt t gases es The trans nsfer er between een zones nes is from turbulent ulent mixing ing and the combus bustion tion progr gres esses es Z Y Z Z Z F F F F F UM PM DIFF PSTOX G. Desoutter, A. Desportes, J. Hira, D. Abouri, M. Zellat
THOE OERE RETIC TICAL AL ECFM-CLEH CLEH MODEL EL DESC SCRIP IPTION: TION: ECFM-CLEH CLEH model : Fundame ndament ntal al appr proac ach h of 4 reactio ion n rates Post-Oxidation Propagation Diffusion flame Auto-ignition G B G F fuel Ox Chemical Kinetics Mixing PDF model TKI-PDF model ECFM model P.D.F : Mixture Fraction FLUCTUATION AI-Saturation Coupling Tables bles for r LFS Chemistry controlled reaction rate Mixing controlled NO Fluctuations reaction rate Flame surface density ITNFS Function Distributed flame with Pdf on mixing scalar (look-up table) G. Desoutter, A. Desportes, J. Hira, D. Abouri, M. Zellat
Autom omotiv tive e DIES ESEL EL ENGIN GINE E B : RES ESULTS TS 5 operating conditions poin int 3 : M : Mid id-load load poin int 1 : F : Full ll lo load poin int 2 : Mid Mid-load load poin int 5 : L Low-load load poin int 4 : L : Low-load load Swir irl l Leve vel l : Fla lap open/closed en/closed G. Desoutter, A. Desportes, J. Hira, D. Abouri, M. Zellat
Autom omotiv tive e DIES ESEL EL ENGIN GINE E B : RESU SULTS TS Emissions NOx-NORA NORA S SOOT OOT CO CO 100 100 100 Experiments 90 90 Experiments 90 Experiments 80 80 80 70 70 STAR-CD 70 STAR-CD STAR-CD 60 (NORA) 60 60 Soot CO NOx 50 50 50 40 40 40 30 30 30 20 20 20 10 10 10 0 0 0 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 G. Desoutter, A. Desportes, J. Hira, D. Abouri, M. Zellat
Autom omotiv tive DIES ESEL EL ENGIN GINE E C : Inject ector or 1 v versus sus Inject ector or 2 Inj nject ection n timing ming variati iation on comparison arison : : SOOT Inje ject ctor or 1 Inje ject ctor or 2 Retarted Injection CLEH EXPE CLEH EXPE 200 50 44 172 45 40 146 150 141 34 34 35 31 116 112 30 26 SOOT SO 100 25 20 79 80 20 15 14 15 50 10 7 6 20 5 10 0 0 0 -4 -2 0 2 4 -4 -2 0 2 4 G. Desoutter, A. Desportes, J. Hira, D. Abouri, M. Zellat
ENG NGINE INE C C : : Inj nject ector or 1 v versus sus Inj nject ctor or 2 Injec ectio tion n timing ming variat iation ion comparis arison on : SOOT T Section ctional al soot model el / PDF Injector 1 Injector 2 Distribution Distribution Soot Diameter Soot Diameter The Soot Sectional Method is capable to differentiate Soot diameter and Distribution between injector 1 and injector 2 G. Desoutter, A. Desportes, J. Hira, D. Abouri, M. Zellat
GDI GDI-GASOLIN GASOLINE: : Real l Engine ngine Wall l Guided ed Multi ti-hole ole inject ector or Equival ivalenc ence ration ion aro round und TDC Spra ray y and d mix ixture ure @ 440 °CA ABDC Red d is is a above ove ER 1. 11 G. Desoutter, A. Desportes, J. Hira, D. Abouri, M. Zellat
GDI-GASOLIN GDI GASOLINE: E: Real l Engine ngine Operat rating ing point nt 1 : : ECM-CLEH CLEH Zoom om on : In In-cylin cylinde der r Pres essur sure Apparen arent Rate e OF Heat at Releas lease In In-cylin cylinder der pres ressur ure e his istory ory (left) t) - Ap Appare parent nt Hear ar Rele leas ase e (right ight) G. Desoutter, A. Desportes, J. Hira, D. Abouri, M. Zellat
Introdu oduction ction of Multi ti-com compone onent nt fuel A single le comp mpon onent ent repres resen enta tativ tive e fuel has been used in the example amples and d validat dation ons shown n in the previou ous section on SI SI-GDI GDI engines ines are e very y sensitiv tive e to the fuel compo mposition ition (evaporation oration process, s, strat atifica icati tion on, , Octa tane numb mber er calibra libration tion using g additiv tives es …) Dual al fuel combu bustion tion is emergin ging, g, especia cially ly in combination ination with Diesel and Natu tura ral gas To get et bet etter er simulation lation of the system m includ ludin ing combu busti tion on chamb mber, fuel compo mpositi ition on and d mixture ture preparati aration on strat ategy gy CD-adapco CD dapco has extend ended ed existing ing combus ustion tion models in STAR AR-CD D to multi ti- compo mponent nent fuel. G. Desoutter, A. Desportes, J. Hira, D. Abouri, M. Zellat
Gasoline oline disti tillati lation on problem lem Lig ight ht Gaso soli line Light Fraction C5 – C6 C6 Heavy Fractio tion RON 60 - 80 80 Toluene Unle leaded Gaso solin ine Crud ude RON 95 - 98 98 Benzene Aromatics MON 85 - 87 87 oïl ïl Heavy vy Gaso soli line C7 – C10 RON 20 - 50 50 Heavy Gasoline Light t Gasol olin ine Boiling Temperature The refiner iner must st im imple lemen ment proces ocesses ses to to im improve rove soline octan ane number er from natura the gasoline ural crude rudes. G. Desoutter, A. Desportes, J. Hira, D. Abouri, M. Zellat
A meric an S ociety ty for T esting nd M aterials rican ting and erials Cooperati perative e Fue uel Rese sear arch h : Distillation tillation process ess Temperature Heated Multi-component Droplet STAR-Simulation % volume ASTM procedure Temperature C1+C2+C3+ C4=anti-knock Agent C1+C2 C1 % volume G. Desoutter, A. Desportes, J. Hira, D. Abouri, M. Zellat
The mult lti-com ompon ponen ent t approac oach h with h ECFM FM-3Z 3Z combu bust stion ion model el g N compon The e liqui uid is repres resent nted d us using ponen ents ts Vapor oriza izati tion on is treat ated ed us using the e discre crete e approach ach For r comb mbusti ustion on: – The molecular weight is computed according to local component concentration taking into account the number of C, H and O in each component – Same treatment for the Enthalpy of formation and Laminar Flame speed For r Aut uto-Igni gniti tion on: 1. When correlation is used: • Ignition delay and auto-ignition rate are balanced by the Octane (cetane) number of each component 2. When tables are used: • Tabulated Kinetic for Ignition technique is used, extracting information directly from the tables G. Desoutter, A. Desportes, J. Hira, D. Abouri, M. Zellat
SI-GD SI GDI I Wall l Guided ed : MULTI TI-COMPONENT COMPONENT COMBUS BUSTION TION Gasoline represented by 4 components Pressure :full cycle Pressure : zoom around TDC Experiment A.R.O.H.R : zoom around TDC A.R.O.H.R :full cycle STAR-CD G. Desoutter, A. Desportes, J. Hira, D. Abouri, M. Zellat
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