Combustion calibration in a Methane port fuel injection engine with the STAR-CD ISSIM embedding the ECFM-3Z model

Transcription

1 Prague Czech Republic March 7-9, 2016 Combustion calibration in a Methane port fuel injection engine with the STAR-CD ISSIM embedding the ECFM-3Z model

2 INDEX 1. PROBLEM PROPOSED 2. ANALYTICAL & NUMERICAL MODELS 3. ISSIM PARAMETERS 4. CALIBRATION POINT 5. RESULTS 6. CONCLUSION Contact:

3 1. PROBLEM PROPOSED

4 PROBLEM PROPOSED Engine main parameters Name TJET 1.4 Number of Cylinders 4 Injection Port fuel Fuel Methane Stroke 84 mm Bore 72 mm Rod Length 129 mm CR 9.8 Operation Points Velocity (rpm) load Calibration point

5 2. ANALYTICAL & NUMERICAL MODELS

6 FUNDAMENTAL EQUATIONS Conservation of mass Conservation of momentum Conservation of energy Dρ Dt = 0 Du Dt = F p ρ Dh Dt = Dp + k T + Φ Dt Combustion CH 4 + 2O 2 CO 2 + 2H 2 O + Q

7 NUMERICAL SOLVER - MESHER ES-ICE Total number of cells Cells inside cylinder Cells for refinement for Combustion Cells in runners 1.1 Mln 0.8 Mln 0.1 Mln 0.3 Mln

8 NUMERICAL SOLVER FLUID DYNAMICS STAR Turbulence model Combustion model Ignition model Wall treatment Laminar flame Speed K-ε Realizable ECFM-3Z ISSIM Algelberger Metghalchi Correlation

9 3. ISSIM PARAMETERS

10 SECONDARY CIRCUIT Secondary Circuit Rs Resistance (Rs): Electrical resistance in the Secondary Circuit [Default value=9000 Ohm] Inductance (Ls): Coil inductance in the Secondary Circuit [Default value=31 mh] Energy (En): Energy in the Secondary Circuit [Default value=0.05 J] FACTEGRVOLT: modification factor of the Voltage according to EGR

11 SECONDARY CIRCUIT Pressure Analysis Ref. Test Peak [bar] % Angle [º] Analysis of Secondary Circuit Parameter Reference Test Energy [J] Resistance [kohm] 9 20 Inductance [mh] Mass flow burnt Ref. Test 10% % %

12 FACTEGRVOLT1 Pressure Analysis Ref. Test 1 Test 2 Peak [bar] % +0.1% Angle [º] Analysis of FACTEGRVOLT1 Reference 4 Test 1 2 Test 2 8 Mass flow burnt Ref. Test 1 Test 2 10% % %

13 LAMINAR SPEED CORRESPONDING TO ISSIM S L corr = δ L 0 l spk + = 4δ L 0 l spk δ L 0 ign 1 + T b l spk 400 S L eff = S L S L corr 1 e 2 x x spk l spk SPINFEXT2 T b ign = Min E b c p b m b, TEMPMAXLCORR SPINFEXT2: Proportional coefficient to adjust the size of the influence sphere for effective laminar flame speed [Default value=1] TEMPMAXCORR: Maximum admissible temperature taken into account for SL correction due to energy provided by spark plug [Default value=5000]

14 SPINFEXT2 Pressure Analysis Ref. Test 1 Test 2 Peak [bar] % 2.62% Angle [º] Analysis of SPINFEXT2 Reference 8 Test 1 4 Test 2 16 Mass flow burnt Ref. Test 1 Test 2 10% % %

15 LAMINAR SPEED CORRESPONDING TO METGHALCHI PRTRANSL: Transition pressure for application of ULAM3 or ULAM3BELOW in the laminar flame speed correlation [Default value=0] ULAM3: Adjustment of pressure ifluence in laminar flame speed correlation for P>PRTRANSL [Default value=40] ULAM3BELOW: adjustment of pressure influence in laminar flame speed correlation for P<PRTRANSL [Default value=60]

16 ULAM3BELOW Pressure Analysis Ref. Test 1 Test 2 Peak [bar] % -4.3% Angle [º] Analysis of ULAM3BELOW Reference 6.5 Test 1 6 Test 2 10 Mass flow burnt Ref. Test 1 Test 2 10% % %

17 CALIBRATION SETTING

18 4. CALIBRATION POINT bar)

19 bar 2000x3 U3B=4.6 SPIN2FEXT=6 Experimental Relative Error Max_P (bar) % Intake mass (g) % Mbf (25.2) (24.7) 0.5 Mbf (36.6) (36.9) 0.3 Mbf (51.1) (50.9) 0.2 T_SA (K) % P_SA (bar) % 120 (intake phase) IMEP Net (bar) IMEP gross (bar) % %

20 bar

21 bar CH

22 5. RESULTS

23 ULAM3BELOW March bar rpm LOAD [BAR]

24 ULAM3BELOW March bar rpm rpm LOAD [BAR]

25 ULAM3BELOW March bar rpm rpm rpm LOAD [BAR]

26 ULAM3BELOW March bar rpm rpm rpm rpm LOAD [BAR]

27 SPINFX2 ULAM3BELOW March 7 9 ALL RESULTS rpm rpm 2570 rpm rpm rpm 2000 rpm 2000 rpm LOAD [BAR] RPM RPM vs SPINFX2

28 SUMMARY RESULTS Error in Intake Mass Error in Pressure at Spark Advance 5% 5% 4% 4% 3% 2% 1% 0% 2.3% 1.9% 1.6% 1.1% 0.6% 0.8% 1.0% 2000x3 2000x x x6 2570x x8 3500x6 3% 2% 1% 0% 2.2% 2.0% 0.8% 0.8% 0.9% 0.2% 0.0% 2000x3 2000x x x6 2570x x8 3500x6 5.00% Error in Peak Pressure 5.00% Error in Temperature at Spark Advance 4.00% 4.00% 3.00% 3.00% 2.00% 1.00% 0.00% 1.28% 1.06% 0.74% 0.56% 0.04% 0.15% 2000x3 2000x x x6 2570x x8 1.21% 3500x6 2.00% 1.00% 0.00% 1.28% 1.06% 0.74% 0.56% 0.04% 0.15% 2000x3 2000x x x6 2570x x8 1.21% 3500x6

29 6. CONCLUSION

30 CONCLUSIONS 1- Development of a model to solve stoichiometric combustion of methane for different operation points.: #Case α u3b spin2 Max peak pressure θ max peak pressure θ 10 θ 50 θ 90 Error Peak Pressure [%] Error θ Peak Pres. [deg] Error θ 10 [deg] Error θ 50 [deg] Error θ 90 [deg] 2000x3 1,6 4,6 6 19,83 375,8 359,2 370,6 385,1 1,28-0,2 0,5-0,3 0,2 2000x3.6 1,6 5,2 4 23,85 374,5 357,8 368,7 382,5-0,04-0,3 0,5 0,0 0,8 2000x4.4 1,6 4,8 4 24,3 377,1 360,6 372,5 388,1-1,06-0,5 0,1 0,1 2,2 2000x6 1,6 6,5 4 34,94 374,7 358,5 369,1 383,9-0,74-0,5-0,1 0,0 2,7 2570x7.9 1,6 7,9 1 43,39 374,8 358,6 369,3 385,1 0,56-0,1 0,2 0,5 2,9 3000x8 1,6 8,25 0,1 48, ,9 365,4 382,4 0,15-0,8-0,9-0,4 4,8 3500x6 1,6 7,25 0,1 36,64 373,4 356,9 367, ,21-0,8-0,3-0,3 3,7

31 FUTURE DEVELOPMENT 1- Introduce new model for laminar speed, DARS: Laminar speed 1.1- Availability to have more accurate results for stoichiometric simulations; possibility of mantaining all parameters (ULAM3BELOW and SPINFEXT2) constant for all operation points Solve combustion for lean mixtures. 2- Extrapolate the results for other engines for similar operation points. 3- Be able to predict the combustion for new engines without experimental sets.

32 DÍKY