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Motivation -",,$,%" ) 7-"+. #33 / $,-$./ #-7- $
Numerical Techniques +,! *+,! ( (!./ -,!,!,! + & & ' # 9:-,- -- *9+>, +,, 9:-,- -- *9+ $-",+ " +(,,, 9:-,- --, "- $ ; ; $ $ < < $ $ = = $," -,- 9:-.,/ - --.,/, -, "-, -,- 9:-.,/ - --.,/ -,, "- %,& -,./,," -,- 9:-,- -- -,, "- %,& -,,," -,- () & * ( & %
D GT-Power Model &,,!?%) -%@), %-%$"!? A)," %-%,,,$,,,,B*C $,"A,,.-,+,,%, /,,,-"-, "",,BDC
Model Validation w/ Head A (/) Cylinder Pressure (bar) RPM WOT RPM WOT RPM WOT 7 D Model 5 3 - -3 5 33 5 - Crank Angle ( CA) Cylinder Pressure (bar) 5 35 3 D Model 5 5 5 - -3 5 33 5 Crank Angle ( CA) Cylinder Pressure (bar) 5 D Model 3 - -3 5 33 5 Crank Angle ( CA) Intake Pressure (bar)..3...9 Intake Pressure (bar).3...9 Intake Pressure (bar)..5 D Model..7 D Model. D Model.95 D Model. - -3 5 33 5 Crank Angle ( CA).7 - -3 5 33 5 Crank Angle ( CA).9 - -3 5 33 5 Crank Angle ( CA)....5...5. Exhaust Pressure (bar)... D Model Exhaust Pressure (bar).3...9. D Model Exhaust Pressure (bar).3...9. D Model.7.7. - -3 5 33 5 Crank Angle ( CA). - -3 5 33 5 Crank Angle ( CA). - -3 5 33 5 Crank Angle ( CA)
Model Validation w/ Head A (/) λ=.3 at rpm w/ PB λ=.3 at rpm w/ PB λ=.5 at rpm w/ PB Cylinder pressure (bar) - - 3 3 5 Crank Angle Degree (ºCA).5 Cylinder Pressure (bar) - - 3 3 5 Crank Angle Degree (º CA). Cylinder Pressure (bar - - 3 3 5 Crank Angle Degree (º CA).55 D Model.5.55.5.5 Intake pressure (bar)..35.3.5 Intake Pressure (bar).5..35.3.5 Intake pressure (bar ).5..35.3.5. - - 3 3 5 Crank angle degree (º CA)..5..5..95.9.5. - - 3 3 5 E xhaust Pressure (bar). - - 3 3 5 Crank Angle Degree (º CA)..5..5..95.9.5. - - 3 3 5 Crank Angle Degree (º CA) E x ha ust P ressure (ba r ). - - 3 3 5 Crank Angle Degree (º CA)..5..5..95.9.5. - - 3 3 5 Crank Angle Degree (º CA) 3
Performance Prediction (Head B ) RPM WOT RPM WOT RPM WOT IMEP (bar) IMEP (bar) IMEP (bar) 5 Spark timing (º CA BTDC) 7 Spark timing (º CA BTDC) 3 9 Spark timing (º CA BTDC) D Model Air mass flow rate (Kg/Hr) 35 3 5 5 5 Air mass flow rate (Kg/Hr) Air mass flow rate (Kg/Hr) Spark timing (º CA BTDC) 7 Spark timing (º CA BTDC) 3 9 Spark timing (º CA BTDC) Fuel mass flow rate (Kg/Hr) 3 Spark timing (º CA BTDC) Fuel mass flow rate (Kg/Hr) 7 5 3 7 Spark timing (º CA BTDC) Fuel mass flow rate (Kg/Hr) 9 7 5 3 3 9 Spark timing (º CA BTDC)
Performance Prediction (Head B ) RPM PT w/ % EGR RPM PT, external EGR sweeps 3 5 Simulation Simulation Pressure (bar) 5 5 Air Mass Flow Rate (Kg/Hr) D Model - - 3 3 5 Crank Angle Degree (ºCA).9 5.3..9. External EGR (%, rpm) 3.5 Simulation.. Simulation Pressure (bar).5.5 Fuel Mass Flow Rate (Kg/Hr).... - - 3 3 5 Crank Angle Degree (ºCA).9 5.3..9. External EGR (%, rpm) 5
*+ Measured intake temperature Measured intake pressure Measured Mass Flow Rate Measured cylinder pressure For calibration Measured exhaust pressure Measured engine speed Measured external EGR Data Communication Calculated Mass Flow Rate D calibrated GT-Power model Measured A/F ratio RGF output Data Communication *
!.. λ # " Calculated Mass Flow Rate [Kg/h] Measured Mass Flow Rate [Kg/h] * ". Calculated Mass Flow Rate [Kg/h]. Measured Mass Flow Rate [Kg/h] Mass Flow Rate (Kg/Hr)..... Mass Flow Rate (Kg/Hr)....... Mass Flow Rate (Kg/Hr). 35. 3. 5.. 5.. 5.....9.3 Lamda (-)..7 5.53 9.75 3..97 EGR (%) # " # 7 Calculated Mass Flow Rate [Kg/h] Measured Mass Flow Rate [Kg/h] Mass Flow Rate (Kg/Hr) 35. 3. 5.. 5.. 5. Calculated Mass Flow Rate [Kg/h] Measured Mass Flow Rate [Kg/h]..5.5.597..99. 5.997 9. NMEP (bar)..5.397.595.3 3..3 5.99.997 NMEP (bar) **
Objective,$,$,"+- %-?,", %, - *#
Semi-empirical Model )E +(, :++9--,*9 5 <". 9 /F3,," :--- :--<".+(,/ --,+ EGR= RGF (%) 3 RGF From Shayler Model RGF From GT-Power 3 5 7 Engine Speed (rpm) )*&&G *$
Effect of Parameters on Density Modifier *%
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RGF Calculation Flow Chart Single cylinder displacement Intake Pressure Before Throttle Overlap Volume (OLV) Exhaust Valve Lift Central Line (ECL) Intake Temperature Before Throttle Calculated Volumetric Efficiency Measured Mass Flow Rate Measured A/F ratio Measured engine speed Measured external EGR Engine Configuration Measure Quantities Engine Compression Ratio Calculated RGF output Semi-Empirical RGF Model *
Calculation Interface in EXCEL *3
Model Validation Various Conditions RGF Predicted by model (%).7 mm intake cam profile Engine speeds ~rpm Fixed OLV Throttle opening ~9º.5% Line -.5% Line RGF Predicted by model (%).3 mm intake cam profile Engine speeds ~rpm Fixed OLV Throttle opening ~9º.5% Line -.5% Line RGF Calculated from GT-Power (%) RGF Calculated from GT-Power (%) RGF Predicted by model (%).9 mm intake cam profile Engine speeds ~rpm Fixed OLV Throttle opening ~9º.5% Line -.5% Line R G F by Em pirica l M o del (% ) 3 5 5 5.3 mm Intake cam profile BMEP varies from bar to WOT Engine speeds ~rpm With OLV variations.5% Line -.5% Line RGF Calculated from GT-Power (%) * 5 5 5 3 RGF Calculated by GT-Power (%)
RGF Prediction at Part Throttle (PT) SAE --353 RGF (%) POR Exhaust manifold GT-Power Calculated Empirical Model Predicted 5 3 RGF(%) GT-Power Calculated Empirical Model Predicted 5 3 Engine Speed (rpm) Engine Speed (rpm) SAE --353 Log-style exhaust manifold *5
RGF Prediction Single Cylinder λ!,! 7 # # ' Residual Gas Fraction (%) Empirical Model FEV Model GT-Power Model....9.3 λ Sweep (-),! &, λ! 7 *9#5%' &: " #*$#$) ;" & < Residual Gas Fraction (%) # Empirical Model FEV Model GT-Power Model.7 5.59 9.7 3..97 External EGR (% )
RGF Prediction Single Cylinder = # #*
Conclusions *, ) -%-%,$"-,"-,, $-%-% * %,, $"$,9-+, -, ",$+,, $,,,-"$-$$"" $$-,,,,.-?,,/"$-,A,, %,,,,% -,"%",+ - $,,'-%, ##
Thank You! #$