low temperature combustion requires high dilution levels
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Low temperature combustion requires highdilution levels - A challenge at high load
Prof. Bengt JohanssonDiv. of Combustion Engines, Dept. of Energy Sciences
Outline
• Lund University
• What is high pressure combustion?
• Why we need high pressure combustion?
• Low temperature combustion– HCCI
– PPC
2
Lund
3
Lund University, Maxlab I-IVEngine lab
European Spallation Source ESS
• 17 partner countries including Sweden and Denmark
• Pre construction Phase started in 2009 and ends in February 2013
• Next phase is the Construction Phase• European Spallation Source will open in
2019 and become fully operational in 2025.
• Total cost: 1.48 Billion €
Outline
• Lund University
• What is high pressure combustion?
• Why we need high pressure combustion?
• Low temperature combustion– HCCI
– PPC
6
What is high pressure combustion?
0
50
100
150
200
250
300
350
-60 -45 -30 -15 0 15 30 45 60 75 90crank angle (CAD)
cylin
der
pre
ssu
re (
bar
)Pressure before combustion =270 bar Peak pressure =300 bar
Data from Prof. Martti Larmi Aalto Univ. Finland
IMEP = 34 bar Goals:Pmax=400 barIMEP=40 bar
Outline
• Lund University
• What is high pressure combustion?
• Why we need high pressure combustion?
• Low temperature combustion– HCCI
– PPC
8
Dilution requires more media
9
Lambda = 3 means an inlet pressure of 3 bar instead of 1 bar going from SI to HCCI burning the same amount of fuel
HCCI dilution operating range
Peak pressure scales with inlet pressure =>
Pmax 240 bar instead of 80 bar with HCCI for same fuel amount burned!
Dilution effect – Simple simulations
1. CA50: 8 [ATDC].
2. CA90-10: 15 [CAD].
3. Engine geometry: standard Scania D13.
4. Inlet temperature: 303 [K].
5. Reference temperature: 298 [K].
6. Engine speed: 1250 [rpm].
7. Differential pressure exhaust minus inlet: 0.25 [bar].
8. Cylinder wall temperature: 450 [K].
9. Heat transfer modeled with the Woschniequation [44]. The C1 and C2 constants were tuned to match the experimental results in [49].
10. The rate of heat release has been approximated with a Wiebe function.
11. EGR is added in order to have 1.35 as λ. If the inlet pressure was not enough to have λ without EGR higher than 1.35, EGR was set to zero.
12. The combustion efficiency was assumed to be 100%.
13. Lower heating value 43.8 MJ/kg, stoichiometric air fuel ratio 14.68.
10
Dilution effect – Less heat losses
11
Experimental results
Inlet Pressure Sweepfocus on efficiency
13
Experimental Set-Up, Scania D12Bosch Common RailPrail 1600 [bar]
Orifices 8 [-]
Orifice Diameter 0.18 [mm]
Umbrella Angle 120° [deg]
Engine / Dyno Specrcgeometric 14.3 [-]
BMEPmax 15 [bar]
Vd 1951 [cm3]
Swirl ratio 2.9 [-]
SAE paper 2010-01-1471
1.5 2 2.5 3 3.544
46
48
50
52
54
56
58G
ross
Indi
cate
d E
ffici
ency
[%]
Abs Inlet Pressure [bar]
FR47338CVXFR47335CVXFR47334CVX
Gross Indicated Efficiency
SAE paper 2010-01-1471
1.5 2 2.5 3 3.520
22
24
26
28
30
32
Exh
aust
Los
s [%
]
Abs Inlet Pressure [bar]
FR47338CVXFR47335CVXFR47334CVX
1.5 2 2.5 3 3.544
46
48
50
52
54
56
58
Gro
ss In
dica
ted
Effi
cien
cy [%
]
Abs Inlet Pressure [bar]
FR47338CVXFR47335CVXFR47334CVX
1.5 2 2.5 3 3.520
22
24
26
28
30
32
Hea
t Tra
nsfe
r [%
]
Abs Inlet Pressure [bar]
FR47338CVXFR47335CVXFR47334CVXIt improves both because of a reduction in heat
transfer and exhaust loss.
Gross Indicated Efficiency
SAE paper 2010-01-1471
EGR Sweepfocus NOx, soot and efficiency
0 10 20 30 40 50 60 702
2.5
3
3.5
4
4.5
Abs
Pin
[bar
]
EGR [%]
0 10 20 30 40 50 60 701.4
1.5
1.6
1.7
l [-]
EGR [%]
FR47338CVXFR47335CVXFR47334CVX
17
The O2 concentration in the inlet, l, was kept constant during the sweep, this was done by adjusting the inlet pressure for a given EGR rate. This was done in order to have soot as a function solely of the EGR rate and not EGR + O2 as in a conventional EGR sweep.
How the sweep was made…
SAE paper 2010-01-1471
0 10 20 30 40 50 60 7050
51
52
53
54
55
56
57
58
59
60
Gro
ss In
dica
ted
Effi
cien
cy [%
]
EGR [%]
FR47338CVXFR47335CVXFR47334CVX
0 10 20 30 40 50 60 7015
17.5
20
22.5
25
27.5
30
Hea
t Tra
nsfe
r [%
]
EGR [%]
FR47338CVXFR47335CVXFR47334CVX
0 10 20 30 40 50 60 7015
17.5
20
22.5
25
27.5
30
Exh
aust
Los
s [%
]
EGR [%]
FR47338CVXFR47335CVXFR47334CVX
By increasing EGR, the indicated efficiency improves as a result of both a decrease in heat transfer and exhaust loss.
Gross Indicated Efficiency
SAE paper 2010-01-1471
0 10 20 30 40 50 60 700
0.5
1
1.5
2
2.5
3
3.5
4
4.5
Soo
t [FS
N]
EGR [%]
FR47338CVXFR47335CVXFR47334CVX
0 10 20 30 40 50 60 700
1
2
3
4
5
6
7
8
spec
ific
NO
x [g
/kW
h]
EGR [%]
FR47338CVXFR47335CVXFR47334CVX
0 10 20 30 40 50 60 7099
99.1
99.2
99.3
99.4
99.5
99.6
99.7
99.8
99.9
100
Com
bust
ion
Effi
cien
cy [%
]
EGR [%]
FR47338CVXFR47335CVXFR47334CVX
Roughly 50% of EGR is necessary to keep NOx below EU VI & US10. The result seems independent on the fuel type. The usual NOx-soot trade off is preset, no soot bump is visible at this load.
The combustion efficiency is higher than 99% even with 60% of EGR è low CO & HC in the exhaust. This is not possible with diesel PPC.
NOx – soot and combustion efficiency
Summary – High Pressure
• What is high pressure combustion?– 275 bar before combustion, 300 bar peak pressure
• Why we need high pressure combustion?– High dilution reduce heat transfer losses
– High dilution reduce exhaust temperature and hence exhaust loss
– Ratio of specific heats less reduced due to combustion. Gives higher efficiency.
– Low NOx
20
Outline
• Lund University
• What is high pressure combustion?
• Why we need high pressure combustion?
• Low temperature combustion– HCCI
– PPC
21
Outline - Low Temperature Combustion
• HCCI and fuel efficiency– 50% thermal efficiency
• Partially premixed combustion, PPC– Background
– Why gasoline is the best diesel engine fuel
– 56% thermal efficiency in car size engine
– 57% thermal efficiency in truck size engine
– Why 55% thermal efficiency is better than 57%
– How to reach 26 bar IMEP with US10 NOx, PM, HC and CO engine out
22
Outline
• HCCI and fuel efficiency– 50% thermal efficiency
• Partially premixed combustion, PPC– Background
– Why gasoline is the best diesel engine fuel
– 56% thermal efficiency in car size engine
– 57% thermal efficiency in truck size engine
– Why 55% thermal efficiency is better than 57%
– How to reach 26 bar IMEP with US10 NOx, PM, HC and CO engine out
23
BackgroundCombustion concepts
Spark Ignition (SI) engine (Gasoline, Otto)
Compression Ignition (CI) engine (Diesel)
+ Clean with 3-way Catalyst
- Poor low & part load efficiency
+ High efficiency- Emissions of NOx and
soot
24
BackgroundCombustion concepts
Spark Ignition (SI) engine (Gasoline, Otto)
Compression Ignition (CI) engine (Diesel)
Homogeneous Charge Compression Ignition
(HCCI)
Partially premixed combustion (PPC)
Diesel HCCI
Spark Assisted Compression Ignition
(SACI)Gasoline HCCI
+ High efficiency
+ Ultra low NOx
-Combustion control
-Power density
+ Injection controlled- Less emissions
advantage
+ Clean with 3-way Catalyst
- Poor low & part load efficiency
+ High efficiency- Emissions of NOx and
soot
25
Efficiencies?
26
Energy flow in an IC engine
FuelMEP
QhrMEP
IMEPgross
lMEPnet
BMEP
QemisMEP
QlossMEP
QhtMEP
QexhMEP
PMEP
FMEP
Combustion efficiency
Thermodynamic efficiency
Gas exchange efficiency
Mechanical efficiency
Net Indicated efficiency
Brake efficiency
Gross Indicated efficiency
FuelMEP
QhrMEP
IMEPgross
lMEPnet
BMEP
QemisMEP
QlossMEP
QhtMEP
QexhMEP
PMEP
FMEP
Combustion efficiency
Thermodynamic efficiency
Gas exchange efficiency
Mechanical efficiency
Net Indicated efficiency
Brake efficiency
Gross Indicated efficiency
hhhhh MechanicaleGasExchangmicThermodynaCombustionBrake***=
27
28
Thermodynamic efficiencySaab SVC variable compression ratio, VCR, HCCI, Rc=10:1-30:1; General Motors L850 “World engine”, HCCI, Rc=18:1, SI, Rc=18:1, SI, Rc=9.5:1 (std) Scania D12 Heavy duty diesel engine, HCCI, Rc=18:1;
Fuel: US regular Gasoline
SAE2006-01-0205
All four efficiencies
29
Outline
• HCCI and fuel efficiency– 50% thermal efficiency
• Partially premixed combustion, PPC– Background
– Why gasoline is the best diesel engine fuel
– 56% thermal efficiency in car size engine
– 57% thermal efficiency in truck size engine
– Why 55% thermal efficiency is better than 57%
– How to reach 26 bar IMEP with US10 NOx, PM, HC and CO engine out
30
Partially Premixed Combustion, PPC
31
-180 -160 -140 -120 -100 -80 -60 -40 -20
1000
2000
3000
4000
5000
6000 y
HC
[ppm
]
SOI [ATDC]-180 -160 -140 -120 -100 -80 -60 -40 -20
200
400
600
800
1000
1200
NO
x [p
pm]
Def: region between truly homogeneous combustion, HCCI, and diffusion controlled combustion, diesel
HCCI
PPC
CIPCCI
Simultaneous OH- and Formaldehyde-LIFVolvo Cars DI diesel in HCCI mode
32
Port HCCI – OH and CH2O
1. Background subtracted2. Remaining noise = 03. Images flattened4. OH (red)
formaldehyde (green)pasted together 33
Port HCCI – OH and CH2O
SAE paper 2004-01-294934
DI HCCI - homogeneity studies
Formaldehyde images acquired at -7 CAD.Numbers above images indicate SOI.
-300 to -80: homogeneous with growing “in-homogeneities as SOI moves later-70 to -50: holes appear-40 to -20: obvious structures. Formaldehyde along cylinder walls.
SAE paper 2005-01-386935
DI HCCI - homogeneity studies
-300 -250 -200 -150 -100 -50 00
0.2
0.4
0.6
0.8
1
Start of Injection (CAD)
Nor
mal
ised
val
ues
-300 -250 -200 -150 -100 -50 00
50
100
150
200
250
300
NO
x (p
pm)
SOI -300 -20 CAD
Homogeneity IndexFormaldehyde surfaceNOx
36
PPC: Effect of EGR with diesel fuel
37
Load 8 bar IMEP
Abs. Inlet Pressure 2.5 bar
Engine Speed 1090 rpm
Swirl Ratio 1.7
Compression Ratio 12.4:1 (Low)
DEER2005
Scania D12 single cylinder
1
43
2
Outline
• HCCI and fuel efficiency– 50% thermal efficiency
• Partially premixed combustion, PPC– Background
– Why gasoline is the best diesel engine fuel
– 56% thermal efficiency in car size engine
– 57% thermal efficiency in truck size engine
– Why 55% thermal efficiency is better than 57%
– How to reach 26 bar IMEP with US10 NOx, PM, HC and CO engine out
39
40
PPC with low cetane diesel
Lic. Thesis by Henrik Nordgren 2005 and presented at DEER2005
Outline
• HCCI and fuel efficiency– 50% thermal efficiency
• Partially premixed combustion, PPC– Background
– Why gasoline is the best diesel engine fuel
– 56% thermal efficiency in car size engine
– 57% thermal efficiency in truck size engine
– Why 55% thermal efficiency is better than 57%
– How to reach 26 bar IMEP with US10 NOx, PM, HC and CO engine out
41
42
VOLVO D5 with Gasoline
-80 -60 -40 -20 0 20 400
50
100
150
CAD [TDC]
Cyl Pressure [bar]Inj Signal [a.u.]RoHR [J/CAD]
N 2000 [rpm]
IMEPg 13.38 [bar]
Pin 2.57 [bar]
Tin 354 [K]
EGR 39 [%]
lambda 1.75 [-]
Injection SOI [TDC] Fuel MEP [bar] Percentage [%]
1 -64.00 10.88 41.28
2 -29.20 7.74 29.36
3 0.80 7.74 29.36
Load NoiseLoad & CA50
Burn rate and ηT
43
Optimum Thermodynamic efficiency
Premixedness
High heat losses
Low effective expansion ratio
-80 -60 -40 -20 0 20 400
50
100
150
CAD [TDC]
Cyl Pressure [bar]Inj Signal [a.u.]RoHR [J/CAD]
44
Efficiencies & Emissions
Indicated Gross Thermal Combustion/240
42
44
46
48
50
52
54
56
58
60
Effi
cien
cy [%
]
91 %
NOx*100 [g/kWh] CO [g/kWh] HC [g/kWh] Soot [FSN]0
5
10
15
20
25
30
35
40
Em
issi
ons
BelowDetectableLevel
13 ppm
0.46 %
4598 ppm
! D60 project goal
dPmax 7.20 [bar/CAD]
CA5 3.40 [TDC]
ID -1.00 [CAD]
CA50 11.35 [TDC]
CA90-10 13.00 [CAD]
Outline
• HCCI and fuel efficiency– 50% thermal efficiency
• Partially premixed combustion, PPC– Background
– Why gasoline is the best diesel engine fuel
– 56% thermal efficiency in car size engine
– 57% thermal efficiency in truck size engine
– Why 55% thermal efficiency is better than 57%
– How to reach 26 bar IMEP with US10 NOx, PM, HC and CO engine out
45
464646
Experimental setup, Scania D12Bosch Common RailPrailmax 1600 [bar]
Orifices 8 [-]
Orifice Diameter 0.18 [mm]
Umbrella Angle 120 [deg]
Engine / Dyno SpecBMEPmax 15 [bar]
Vd 1951 [cm3]
Swirl ratio 2.9 [-]
Fuel: Gasoline or Ethanol
47474747
Fuel amount in the pilot is a function of:1.rc2.RON/MON3.EGR
-60 -50 -40 -30 -20 -10 0 100
0.2
0.4
0.6
0.8
1
CAD [TDC]
[a.u
.]
Load & CA50Const.
It must not react during compression
Injection StrategyIt consists of two injections. The first one is placed @ -60 TDC to create a homogeneous mixture while the second around TDC. The stratification created by the second injection triggers the combustion. The first injection must not react during the compression stroke, this is achieved by using EGR.
SAE 2009-01-0944
4848
IMEP sweep @ 1300 [rpm]EGR ~ const throughout the sweep, 40-50 [%]l~ const throughout the sweep, 1.5-1.6 [-]Tin = 308 [K]
Standard piston bowl, rc: 17:1
High Compression Ratio PPC
SAE 2009-01-2668
49
Running Conditions
4 5 6 7 8 9 10 11 12 131.5
1.75
2
2.25
2.5
Gross IMEP [bar]
[bar
]
4 5 6 7 8 9 10 11 12 130
50
100
150
200
250
300
350
[C]Inlet Pressure
Exhaust Pressure
Inlet TemperatureExhaust Temperature
4 5 6 7 8 9 10 11 12 131.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
2
Gross IMEP [bar]l
[-]4 5 6 7 8 9 10 11 12 13
30
35
40
45
50
55
60
EG
R [%
]
5050
Efficiencies
4 5 6 7 8 9 10 11 12 1350
55
60
65
70
75
80
85
90
95
100
Gross IMEP [bar]
[%] Combustion Efficiency
Thermal EfficiencyGas Exchange EfficiencyMechanical Efficiency
512 4 6 8 10 12 14
0
2
4
6
8
10
12
14
16
18
Gross IMEP [bar]
CO
[g/k
Wh]
GrossNetBrakeEU VIUS 10
2 4 6 8 10 12 140
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
Sm
oke
[FS
N]
Gross IMEP [bar]
512 4 6 8 10 12 14
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
Gross IMEP [bar]
HC
[g/k
Wh]
GrossNetBrakeEU VIUS 10
EmissionsObsolete injection system
Not well tuned EGR-lcombination
2 4 6 8 10 12 140
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
Gross IMEP [bar]
NO
x [g
/kW
h]
GrossNetBrakeEU VIUS 10
Outline
• HCCI and fuel efficiency– 50% thermal efficiency
• Partially premixed combustion, PPC– Background
– Why gasoline is the best diesel engine fuel
– 56% thermal efficiency in car size engine
– 57% thermal efficiency in truck size engine
– Why 55% thermal efficiency is better than 57%
– How to reach 26 bar IMEP with US10 NOx, PM, HC and CO engine out
52
5353
Low Compression Ratio PPC
IMEP sweep @ 1300 [rpm]EGR ~ const throughout the sweep, 40-50 [%]l~ const throughout the sweep, 1.5-1.6 [-]Tin = 308 [K]
Custom piston bowl, rc: 14.3:1
SAE 2010-01-0871
5454
4 6 8 10 12 14 16 1850
55
60
65
70
75
80
85
90
95
100
Gross IMEP [bar]
[%] Combustion Efficiency
Thermal EfficiencyGas Exchange EfficiencyMechanical Efficiency
Efficiencies
5555
4 6 8 10 12 14 16 180
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
Sm
oke
[FS
N]
Gross IMEP [bar]2 4 6 8 10 12 14 16 18
0
0.1
0.2
0.3
0.4
0.5
0.6
Gross IMEP [bar]
NO
x [g
/kW
h]
GrossNetBrakeEU VIUS 10
2 4 6 8 10 12 14 16 180
1
2
3
4
5
6
7
8
9
10
Gross IMEP [bar]
CO
[g/k
Wh]
GrossNetBrakeEU VIUS 10
2 4 6 8 10 12 14 16 180
0.3
0.6
0.9
1.2
1.5
Gross IMEP [bar]
HC
[g/k
Wh]
GrossNetBrakeEU VIUS 10
Emissions
Better tuned EGR-lcombination
Fuel Effects on High ON Fuels PPC
Prof. Bengt JohanssonDivision of Combustion EnginesDepartment of Energy Sciences
Lund University56
5757
Fuel specification
RON MON C H/C O/C LHV [MJ/kg] A/F stoich
Ethanol 107 89 2 3 0.5 26.9 9
FR47330CVX 87.1 80.5 7.2 1.92 0 43.5 14.6
FR47331CVX 92.9 84.7 6.9 1.99 0.03 41.6 14.02
FR47333CVX 80.0 75.0 7.16 1.97 0 43.7 14.65
FR47334CVX 69.4 66.1 7.11 1.98 0 43.8 14.68
FR47335CVX 99 96.9 7.04 2.28 0 44.3 15.1
FR47336CVX 70.3 65.9 7.1 2.08 0 43.8 14.83
FR47338CVX 88.6 79.5 7.21 1.88 0 43.5 14.53
57
5858
Inlet Conditions
2 4 6 8 10 12 14 16 18 20300
320
340
360
380
400
420
440
Gross IMEP [bar]
Inle
t Tem
pera
ture
[K]
EthanolFR47330CVXFR47331CVXFR47333CVXFR47334CVXFR47335CVXFR47336CVXFR47338CVX
2 4 6 8 10 12 14 16 18 200.5
1
1.5
2
2.5
3
3.5
4
Gross IMEP [bar]
abs
Inle
t Pre
ssur
e [b
ar]
EthanolFR47330CVXFR47331CVXFR47333CVXFR47334CVXFR47335CVXFR47336CVXFR47338CVX
2 4 6 8 10 12 14 16 18 200
10
20
30
40
50
60
Gross IMEP [bar]
EG
R [%
] EthanolFR47330CVXFR47331CVXFR47333CVXFR47334CVXFR47335CVXFR47336CVXFR47338CVX
2 4 6 8 10 12 14 16 18 201
1.5
2
2.5
3
3.5
4
4.5
Gross IMEP [bar]
l [-]
EthanolFR47330CVXFR47331CVXFR47333CVXFR47334CVXFR47335CVXFR47336CVXFR47338CVX
58
59
Injection strategy
2 4 6 8 10 12 14 16 18 200
5
10
15
20
25
30
35
40
Gross IMEP [bar]
Fuel
ME
P m
ain
[bar
]
EthanolFR47330CVXFR47331CVXFR47333CVXFR47334CVXFR47335CVXFR47336CVXFR47338CVX
2 4 6 8 10 12 14 16 18 200
5
10
15
20
25
30
35
40
Gross IMEP [bar]
Fuel
ME
P p
ilot [
bar]
EthanolFR47330CVXFR47331CVXFR47333CVXFR47334CVXFR47335CVXFR47336CVXFR47338CVX
-60 -50 -40 -30 -20 -10 0 100
0.2
0.4
0.6
0.8
1
CAD [TDC]
[a.u.]
59
60
Efficiencies
2 4 6 8 10 12 14 16 18 2095
95.5
96
96.5
97
97.5
98
98.5
99
99.5
100
Gross IMEP [bar]
Com
bust
ion
Effi
cien
cy [%
]
EthanolFR47330CVXFR47331CVXFR47333CVXFR47334CVXFR47335CVXFR47336CVXFR47338CVX
2 4 6 8 10 12 14 16 18 2040
42
44
46
48
50
52
54
56
58
60
Gross IMEP [bar]
Gro
ss In
dica
ted
Effi
cien
cy [%
]
EthanolFR47330CVXFR47331CVXFR47333CVXFR47334CVXFR47335CVXFR47336CVXFR47338CVX
2 4 6 8 10 12 14 16 18 2040
42
44
46
48
50
52
54
56
58
60
Gross IMEP [bar]
Ther
mal
Effi
cien
cy [%
]
EthanolFR47330CVXFR47331CVXFR47333CVXFR47334CVXFR47335CVXFR47336CVXFR47338CVX
60
61
Emissions – different fuels
2 4 6 8 10 12 14 16 18 200
0.5
1
1.5
2
2.5
Gross IMEP [bar]
Soo
t [FS
N]
EthanolFR47330CVXFR47331CVXFR47333CVXFR47334CVXFR47335CVXFR47336CVXFR47338CVX
2 4 6 8 10 12 14 16 18 200
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
Gross IMEP [bar]
NO
x [g
/kW
h]
EthanolFR47330CVXFR47331CVXFR47333CVXFR47334CVXFR47335CVXFR47336CVXFR47338CVX
2 4 6 8 10 12 14 16 18 200
2
4
6
8
10
12
Gross IMEP [bar]
CO
[g/k
Wh]
EthanolFR47330CVXFR47331CVXFR47333CVXFR47334CVXFR47335CVXFR47336CVXFR47338CVX
2 4 6 8 10 12 14 16 18 200
1
2
3
4
5
6
7
8
9
10
Gross IMEP [bar]
HC
[g/k
Wh]
EthanolFR47330CVXFR47331CVXFR47333CVXFR47334CVXFR47335CVXFR47336CVXFR47338CVX
Outline
• HCCI and fuel efficiency– 50% thermal efficiency
• Partially premixed combustion, PPC– Background
– Why gasoline is the best diesel engine fuel
– 56% thermal efficiency in car size engine
– 57% thermal efficiency in truck size engine
– Why 55% thermal efficiency is better than 57%
– How to reach 26 bar IMEP with US10 NOx, PM, HC and CO engine out
62
6363
Experimental Apparatus, Scania D13XPI Common RailOrifices 8 [-]
Orifice Diameter 0.19 [mm]
Umbrella Angle 148 [deg]
Engine / Dyno SpecBMEPmax 25 [bar]
Vd 2124 [cm3]
Swirl ratio 2.095 [-]
Standard piston bowl, rc: 17.3:1
645 10 15 20 25 3040
50
60
70
80
90
100
Gross IMEP [bar]
[%]
h combustionh gas exchangeh thermalh mechanical
Efficiency
hhhhh MechanicaleGasExchangmicThermodynaCombustionBrake×××=
50% brake efficiency è maximization of all intermediate efficiencies
RoHR, Cylinder Pressure & Injection Signal
-60 -40 -20 0 20 40 600
50
100
150
200
250
CAD [TDC]
IMEPg: 5 [bar]
lambda: 1.57 [-]EGR: 42.66 [%]CA50: 9.71 [TDC]COV: 2.2 [%]eta comb: 94.16 [%]NOx: 0.108 [g/kWh]HC: 2.7 [g/kW]CO: 23 [g/kW]Soot: 0.0033 [FSN]
Abs Pin: 1.07 [bar]Abs Pex: 1.15 [bar]Tin: 308 [K]Tex: 521 [K]
RoHR/3 [J/CAD]Cylinder Pressure [bar]Injection Current [a.u.]
-60 -40 -20 0 20 40 600
50
100
150
200
250
CAD [TDC]
IMEPg: 26 [bar]
lambda: 1.32 [-]EGR: 47.98 [%]CA50: 13.9 [TDC]COV: 0.56 [%]eta comb: 99.89 [%]NOx: 0.264 [g/kWh]HC: 0.091 [g/kW]CO: 0.31 [g/kW]Soot: 0.26 [FSN]
Abs Pin: 3.64 [bar]Abs Pex: 4.01 [bar]Tin: 293 [K]Tex: 673 [K]
RoHR/3 [J/CAD]Cylinder Pressure [bar]Injection Current [a.u.]
-60 -40 -20 0 20 40 600
50
100
150
200
250
CAD [TDC]
IMEPg: 20 [bar]
lambda: 1.37 [-]EGR: 53.22 [%]CA50: 9.27 [TDC]COV: 0.7 [%]eta comb: 99.89 [%]NOx: 0.201 [g/kWh]HC: 0.082 [g/kW]CO: 0.31 [g/kW]Soot: 0.21 [FSN]
Abs Pin: 3.21 [bar]Abs Pex: 3.48 [bar]Tin: 293 [K]Tex: 606 [K]
RoHR/3 [J/CAD]Cylinder Pressure [bar]Injection Current [a.u.]
-60 -40 -20 0 20 40 600
50
100
150
200
250
CAD [TDC]
IMEPg: 16 [bar]
lambda: 1.36 [-]EGR: 46.69 [%]CA50: 7.6 [TDC]COV: 0.58 [%]eta comb: 99.82 [%]NOx: 0.281 [g/kWh]HC: 0.1 [g/kW]CO: 0.63 [g/kW]Soot: 0.31 [FSN]
Abs Pin: 2.35 [bar]Abs Pex: 2.88 [bar]Tin: 292 [K]Tex: 623 [K]
RoHR/3 [J/CAD]Cylinder Pressure [bar]Injection Current [a.u.]
-60 -40 -20 0 20 40 600
50
100
150
200
250
CAD [TDC]
IMEPg: 11 [bar]
lambda: 1.48 [-]EGR: 46.41 [%]CA50: 6.82 [TDC]COV: 1.2 [%]eta comb: 99.4 [%]NOx: 0.317 [g/kWh]HC: 0.22 [g/kW]CO: 2.6 [g/kW]Soot: 0.05 [FSN]
Abs Pin: 1.76 [bar]Abs Pex: 2.73 [bar]Tin: 291 [K]Tex: 612 [K]
RoHR/3 [J/CAD]Cylinder Pressure [bar]Injection Current [a.u.]
65
RoHR, Cylinder Pressure & Injection Signal
-60 -40 -20 0 20 40 600
50
100
150
200
250
CAD [TDC]
IMEPg: 5 [bar]
lambda: 1.57 [-]EGR: 42.66 [%]CA50: 9.71 [TDC]COV: 2.2 [%]eta comb: 94.16 [%]NOx: 0.108 [g/kWh]HC: 2.7 [g/kW]CO: 23 [g/kW]Soot: 0.0033 [FSN]
Abs Pin: 1.07 [bar]Abs Pex: 1.15 [bar]Tin: 308 [K]Tex: 521 [K]
RoHR/3 [J/CAD]Cylinder Pressure [bar]Injection Current [a.u.]
66
RoHR, Cylinder Pressure & Injection Signal
-60 -40 -20 0 20 40 600
50
100
150
200
250
CAD [TDC]
IMEPg: 11 [bar]
lambda: 1.48 [-]EGR: 46.41 [%]CA50: 6.82 [TDC]COV: 1.2 [%]eta comb: 99.4 [%]NOx: 0.317 [g/kWh]HC: 0.22 [g/kW]CO: 2.6 [g/kW]Soot: 0.05 [FSN]
Abs Pin: 1.76 [bar]Abs Pex: 2.73 [bar]Tin: 291 [K]Tex: 612 [K]
RoHR/3 [J/CAD]Cylinder Pressure [bar]Injection Current [a.u.]
67
RoHR, Cylinder Pressure & Injection Signal
-60 -40 -20 0 20 40 600
50
100
150
200
250
CAD [TDC]
IMEPg: 16 [bar]
lambda: 1.36 [-]EGR: 46.69 [%]CA50: 7.6 [TDC]COV: 0.58 [%]eta comb: 99.82 [%]NOx: 0.281 [g/kWh]HC: 0.1 [g/kW]CO: 0.63 [g/kW]Soot: 0.31 [FSN]
Abs Pin: 2.35 [bar]Abs Pex: 2.88 [bar]Tin: 292 [K]Tex: 623 [K]
RoHR/3 [J/CAD]Cylinder Pressure [bar]Injection Current [a.u.]
68
RoHR, Cylinder Pressure & Injection Signal
-60 -40 -20 0 20 40 600
50
100
150
200
250
CAD [TDC]
IMEPg: 20 [bar]
lambda: 1.37 [-]EGR: 53.22 [%]CA50: 9.27 [TDC]COV: 0.7 [%]eta comb: 99.89 [%]NOx: 0.201 [g/kWh]HC: 0.082 [g/kW]CO: 0.31 [g/kW]Soot: 0.21 [FSN]
Abs Pin: 3.21 [bar]Abs Pex: 3.48 [bar]Tin: 293 [K]Tex: 606 [K]
RoHR/3 [J/CAD]Cylinder Pressure [bar]Injection Current [a.u.]
69
RoHR, Cylinder Pressure & Injection Signal
-60 -40 -20 0 20 40 600
50
100
150
200
250
CAD [TDC]
IMEPg: 26 [bar]
lambda: 1.32 [-]EGR: 47.98 [%]CA50: 13.9 [TDC]COV: 0.56 [%]eta comb: 99.89 [%]NOx: 0.264 [g/kWh]HC: 0.091 [g/kW]CO: 0.31 [g/kW]Soot: 0.26 [FSN]
Abs Pin: 3.64 [bar]Abs Pex: 4.01 [bar]Tin: 293 [K]Tex: 673 [K]
RoHR/3 [J/CAD]Cylinder Pressure [bar]Injection Current [a.u.]
70
7171
5 10 15 20 25 300
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
Gross IMEP [bar]
Soo
t [FS
N]
Emissions
0 5 10 15 20 25 300
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
Gross IMEP [bar]
Bra
ke H
C [g
/kW
h]
Brake HCUS 10EU VI
0 5 10 15 20 25 300
0.1
0.2
0.3
0.4
0.5
0.6
Gross IMEP [bar]
Bra
ke N
Ox
[g/k
Wh]
Brake NOxUS10EU VI
0 5 10 15 20 25 300
5
10
15
20
25
Gross IMEP [bar]
Bra
ke C
O [g
/kW
h]
Brake COUS 10EU VI
727272
RON MON C H/C O/C LHV [MJ/kg] A/F stoichGroup 1 FR47335CVX 99.0 96.9 7.04 2.28 0.00 44.30 15.10
FR47332CVX 97.7 87.5 6.61 2.06 0.07 39.70 13.44
FR47337CVX 96.5 86.1 7.53 1.53 0.00 42.10 14.03
Group 2 FR47338CVX 88.6 79.5 7.21 1.88 0.00 43.50 14.53
FR47330CVX 87.1 80.5 7.20 1.92 0.00 43.50 14.60
FR47331CVX 92.9 84.7 6.90 1.99 0.03 41.60 14.02
Group 3 FR47336CVX 70.3 65.9 7.10 2.08 0.00 43.80 14.83
FR47334CVX 69.4 66.1 7.11 1.98 0.00 43.80 14.68
FR47333CVX 80.0 75.0 7.16 1.97 0.00 43.70 14.65
Group 4 PRF20 20 20 7.2 2.28 0 44.51 15.07
MK1 n.a. 20 16 1.87 0 43.15 14.9
Fuel Matrix
737373
20 30 40 50 60 70 80 90 1000
5
10
15
20
25
RON [-]
IME
P g
ross
[bar
]
Stable operational load vs. fuel type
Tested Load Area
0 5 10 15 20 25 300
0.5
1
1.5
2
2.5
3
Gross IMEP [bar]
Soot
[FSN
]
G. ON 99/97G. ON 98/88G. ON 97/86G. ON 93/85G. ON 89/80G. ON 87/81G. ON 80/75G. ON 70/66G. ON 69/66D. CN 52PRF20
Diesel vs. Gasoline
747474
Soot Emissions
75
Summary
76
Engine combustion - direction
Spark Ignition (SI) engine (Gasoline,
Otto)
Compression Ignition (CI) engine
(Diesel)
Homogeneous Charge
Compression Ignition (HCCI)
Diesel PPC
+ High Efficiency
+ Ultralow NOx & soot
- Combustion control
- Power density
+ Clean with 3-way Catalyst
- Poor low & part load efficiency
+ High efficiency- Emissions of NOx
and soot
+ Injection controlled- Efficiency at high load
Gasoline PPC
+ High Efficiency+ Low NOx & soot
1900-1995
1995-2005
2005-2010
2010-
The End
Thank you
77
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