W01
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UNIVERSITY OF WISCONSIN - ENGINE RESEARCH CENTER Reactivity Controlled Compression Ignition Combustion in a Heavy-Duty Engine R. M. Hanson, R. D. Reitz Funding Sponsor : US Department of Energy RCCI Motivation Injection Setup 9 bar SOI1 SWEEP 3401E SCOTE Geometry 9.1:1 Effective Compression Ratio Stock Piston Bowl Geometry Articulated Piston Type 0.7 Swirl Ratio (stock) 335.00 IVO (deg ATDC) 85.00 IVC (deg BTDC) (modified cam) 4 Number of Valves 1.57 Squish Height (mm) 261.60 Connecting Rod Length (mm) 165.10 Stroke (mm) 137.20 Bore (mm) 16.1:1 Geometric Compression Ratio 2.44 Displacement (l) 9 Bar Gas % Sweep High Load Ethanol/Diesel Conclusions Engine experiments showed RCCI combustion to be controlled by SOI timing and/or by the low reactivity-to-high reactivity fuel split. Thermal efficiencies over 50% were shown to be possible from 9 bar IMEP to 16 bar IMEP Over the same range, it was possible to achieve NOx and PM emissions below EPA 2010 heavy-duty limits. High reactivity fuel Low reactivity fuel 750 [cc/min] Steady Flowrate 3 Number of Holes 15° Included Spray Angle 0.5 Injection Pressure [MPa] Port Type BOSCH Manufacturer Low Pressure Injector High Pressure Injector 1500 Injection Pressure [bar] DSLA95PV3387517 Nozzle Part Number 1000 Steady Flowrate [cc/30 sec] at 100 bar 250 Hole Diameter [μm] 6 Number of Holes 145° Included Spray Angle Gen 2 Common Rail Body Type BOSCH MFG -30 -20 -10 0 10 20 30 40 50 0 2 4 6 8 10 12 14 16 Experiment Simulation Crank [°ATDC] Pressure [MPa] 0 200 400 600 800 1000 1200 1400 1600 62 58 AHRR [J/°] SOI1 = Sweep SOI2 = -37 ° ATDC 55 0.0 0.1 0.2 0.3 0.000 0.004 0.008 0.012 0 4 8 12 0 4 8 12 160 170 180 -62 -61 -60 -59 -58 -57 -56 -55 5 10 15 NOx [g/kW-hr] soot [g/kW-hr] 2010 HD Limit HC [g/kW-hr] CO [g/kW-hr] Net ISFC [g/kW-hr] Experiment Simulation PRR [bar/deg] SOI1 [°ATDC] •Low NOx and PM emissions •High efficiency (50%) •NOx and PRR increase with retarded SOI1 timing •Higher combustion temperatures with retarded SOI1 •Higher local equivalence ratio and reactivity advance combustion and increase NOx emissions •Data from SAE 2010- 01-0864 and Thiesel 2010 -20 -10 0 10 20 0 20 40 60 80 100 120 140 160 Increase Gas % Crank [°ATDC] Pressure [Bar] 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 82% 86% AHRR [kJ/°] SOI1 = -58 ° ATDC SOI2 = -37 ° ATDC IVC = -143 89% 0.0 0.1 0.2 0.3 0.000 0.005 0.010 0.015 156 158 160 162 164 0 1 2 3 4 81 82 83 84 85 86 87 88 89 90 0 2 4 6 8 6 9 12 15 NOx [g/kW-hr] PM [g/kW-hr] US EPA 2010 H-D limit US EPA 2010 H-D limit Net ISFC [g/kW-hr] HC [g/kW-hr] CO [g/kW-hr] Gasoline Percentage [% of total fuel ] PRR [bar/deg] • Low NOx and PM emissions - Below EPA 2010 • High thermal efficiency of 53% • PRR drop with additional gasoline due to delayed combustion phasing -25 -20 -15 -10 -5 0 5 10 15 20 25 30 0 20 40 60 80 100 120 140 E-85/Diesel 16.5 IMEPg 43 % EGR Mid and High Load Gasoline/Diesel 9.6 IMEPg 43% EGR Pressure (bar) Crank Angle (° ° ° CA ATDC) NTC Behavior E-85/Diesel 9.6 IMEPg 0% EGR 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 AHRR (kJ/ ° ° ° ° CA) -20 -15 -10 -5 0 0.00 0.01 0.02 0.03 0.04 0.05 AHRR ( kJ/ ° ° ° ° CA ) Crank Angle ( ° °° ° CA ATDC ) 4 6 8 10 12 14 16 18 0.46 0.48 0.50 0.52 0.54 0.56 0.58 0.60 140 150 160 170 180 -2 0 2 4 6 8 10 12 6 8 10 12 14 16 18 20 22 η η η ηg indicated (-) IMEPg (bar) ISFCg gasoline eq.(g/Kw-hr) gasoline/1.75 % DTBP gasoline E-85/diesel gasoline/diesel CA50 ( ° ° ° ° CA ATDC) HTHR Combustion duration 5-90 ( ° ° ° ° CA) • High load operation (16.5 bar IMEPg) with Ethanol/Diesel blends was possible • EGR not required for 9.6 or 11.5 bar IMEPg with E-85 • Longer combustion durations for ethanol blends • CA50 linearly increases with load, keeps PRR and peak cylinder pressure within limits • Greater than 50% thermal efficiency at nearly all operating conditions • Change fuel reactivity by blending fuels in-cylinder. • Increase combustion duration via fuel reactivity gradient. • Extend operating range of PCCI combustion. -25 -20 -15 -10 -5 0 5 10 15 20 25 0 20 40 60 80 100 120 140 Pressure (bar) Crank Angle (° ° ° CA ATDC) NTC behavior 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 AHRR (kJ/ ° ° ° ° CA) -25 -20 -15 -10 -5 0 0.00 0.01 0.02 0.03 0.04 0.05 AHRR ( kJ/ ° ° ° ° CA ) Crank Angle ( ° °° ° CA ATDC ) Speed Load Premixed
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w01
Transcript of W01
UNIVERSITY OF WISCONSIN - ENGINE RESEARCH CENTER
Reactivity Controlled Compression Ignition Combustion in a Heavy-Duty EngineR. M. Hanson, R. D. Reitz Funding Sponsor : US Department of Energy
RCCI MotivationInjection Setup
9 bar SOI1 SWEEP
3401E SCOTE Geometry
9.1:1Effective Compression Ratio
StockPiston Bowl Geometry
Articulated Piston Type
0.7Swirl Ratio (stock)
335.00 IVO (deg ATDC)
85.00IVC (deg BTDC) (modified cam)
4Number of Valves
1.57Squish Height (mm)
261.60Connecting Rod Length (mm)
165.10Stroke (mm)
137.20Bore (mm)
16.1:1Geometric Compression Ratio
2.44Displacement (l)
9 Bar Gas % Sweep High Load Ethanol/Diesel Conclusions
Engine experiments showed RCCI combustion to be controlled by SOI timing and/or by the low reactivity-to-high reactivity fuel split.
Thermal efficiencies over 50% were shown to be possible from 9 bar IMEP to 16 bar IMEP
Over the same range, it was possible to achieve NOx and PM emissions below EPA 2010 heavy-duty limits.
High reactivity fuel
Low reactivity fuel
750 [cc/min]Steady Flowrate
3Number of Holes
15°Included Spray Angle
0.5Injection Pressure [MPa]
PortType
BOSCHManufacturer
Low Pressure InjectorHigh Pressure Injector
1500Injection Pressure [bar]
DSLA95PV3387517Nozzle Part Number
1000 Steady Flowrate [cc/30 sec] at 100 bar
250Hole Diameter [µm]
6Number of Holes
145°Included Spray Angle
Gen 2 Common RailBody Type
BOSCH MFG
-30 -20 -10 0 10 20 30 40 500
2
4
6
8
10
12
14
16
Experiment Simulation
Crank [°ATDC]
Pre
ssur
e [M
Pa]
0
200
400
600
800
1000
1200
1400
1600
6258
AH
RR
[J/°
]
SOI1 = SweepSOI2 = -37°ATDC
55
0.0
0.1
0.2
0.3
0.000
0.004
0.008
0.012
0
4
8
12
0
4
8
12
160
170
180
-62 -61 -60 -59 -58 -57 -56 -555
10
15
NO
x[g
/kW
-hr]
soot
[g/k
W-h
r]
2010 HD Limit
HC
[g/k
W-h
r]
CO
[g/k
W-h
r]
Net
ISF
C[g
/kW
-hr]
Experiment Simulation
PR
R[b
ar/d
eg]
SOI1 [°ATDC]
•Low NOx and PM emissions
•High efficiency (50%)
•NOx and PRR increase with retarded SOI1 timing
•Higher combustion temperatures with retarded SOI1
•Higher local equivalence ratio and reactivity advance combustion and increase NOx emissions
•Data from SAE 2010-01-0864 and Thiesel2010
-20 -10 0 10 200
20
40
60
80
100
120
140
160
Increase Gas %
Crank [°ATDC]
Pre
ssur
e [B
ar]
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
82%
86%
AH
RR
[kJ/
°]
SOI1 = -58°ATDCSOI2 = -37°ATDCIVC = -143
89%
0.00.10.20.3
0.0000.0050.0100.015
156158160162164
01234
81 82 83 84 85 86 87 88 89 9002468
69
1215
NO
x[g
/kW
-hr]
PM
[g/k
W-h
r] US EPA 2010 H-D limit
US EPA 2010 H-D limit
Net
ISF
C[g
/kW
-hr]
HC
[g/k
W-h
r]
CO
[g/k
W-h
r]
Gasoline Percentage [% of total fuel ]
PR
R[b
ar/d
eg]
• Low NOx and PM emissions
- Below EPA 2010
• High thermal efficiency of 53%
• PRR drop with additional gasoline due to delayed combustion phasing
-25 -20 -15 -10 -5 0 5 10 15 20 25 30
0
20
40
60
80
100
120
140
E-85/Diesel16.5 IMEPg43% EGR
Mid and High Load
Gasoline/Diesel9.6 IMEPg43% EGR
Pre
ssu
re (
bar
)
Crank Angle (°°°° CA ATDC)
NTC Behavior
E-85/Diesel9.6 IMEPg0% EGR 0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
AH
RR
(kJ
/ °° °° C
A)-20 -15 -10 -5 0
0.00
0.01
0.02
0.03
0.04
0.05
AH
RR
(kJ
/ °° °° C
A)
Crank Angle (°°°° CA ATDC)
4 6 8 10 12 14 16 18
0.460.480.500.520.540.560.580.60 140
150
160
170
180-202468
1012 6
810121416182022
ηη ηηg in
dic
ated
(-)
IMEPg (bar)
ISF
Cg
gas
olin
e eq
.(g
/Kw
-hr)
gasoline/1.75 % DTBP gasoline E-85/diesel gasoline/diesel
CA
50 (
°° °° C
A A
TD
C)
HT
HR
Co
mb
ust
ion
du
rati
on
5-9
0 ( °° °°
CA
)
• High load operation
(16.5 bar IMEPg) with Ethanol/Diesel blends
was possible
• EGR not required for 9.6 or 11.5 bar IMEPg with
E-85
• Longer combustion
durations for ethanol blends
• CA50 linearly increases
with load, keeps PRR and peak cylinder
pressure within limits
• Greater than 50% thermal efficiency at
nearly all operating
conditions
• Change fuel reactivity by blending fuels in-cylinder.
• Increase combustion duration via fuel reactivity gradient.
• Extend operating range of PCCI combustion.
-25 -20 -15 -10 -5 0 5 10 15 20 25
0
20
40
60
80
100
120
140
Pre
ssu
re (
bar
)
Crank Angle (°°°° CA ATDC)
NTC behavior
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
AH
RR
(kJ
/ °° °° C
A)-25 -20 -15 -10 -5 0
0.000.010.020.030.040.05
AH
RR
(kJ
/ °° °° C
A)
Crank Angle (°°°° CA ATDC)
Speed
Load
Premixed
