For the two-stroke marine diesel engine, the action of exhaust valve has a significant impact on scavenging and combustion processes and ultimately affects the engine performances and emissions. In order to reduce nitrogen oxides (NOx) emissions of a two-stroke marine diesel engine, different exhaust valve lifts (EVLs) were achieved by computational fluid dynamics simulation method in this study. The NOx reduction effect and influence mechanism of EVL on a two-stroke marine diesel engine were investigated in detail. The results showed that the in-cylinder residual exhaust gas and the internal exhaust gas recirculation (EGR) rate gradually increased with the decreasing EVL. Although the total mass of charge enclosed in the cylinder did not change much, the composition changed gradually and the maximum internal EGR rate reached 13.17% in this study. The maximum compression pressure and combustion pressure both rose first and then decreased with the decreasing EVL. While the start of combustion and the maximum combustion temperature were basically unaffected by EVL, the indicated power of the engine was also not much impacted when the EVL was changed from increasing 10 mm to decreasing 20 mm. The indicated specific fuel consumption first declined slowly and then rose rapidly as the EVL reduction exceeded 20 mm. NOx emissions decreased monotonously with the decreasing EVL. The reduction of NOx formation rate and the amount of NOx formation mass mainly occurred at the middle and late stages of combustion for the downward moving of residual exhaust gas. NOx emissions were reduced by 12.57% without compromising other engine performances at medium-reduced EVL in this study. However, in order to further reduce NOx emissions at low EVLs, other measures may be needed to make the residual exhaust gas more evenly distributed during the initial stage of combustion.

References

References
1.
Corbett
,
J. J.
,
Winebrake
,
J. J.
,
Green
,
E. H.
,
Kasibhatla
,
P.
,
Eyring
,
V.
, and
Lauer
,
A.
,
2007
, “
Mortality From Ship Emissions: A Global Assessment
,”
Environ. Sci. Technol.
,
41
(
24
), pp.
8512
8518
.
2.
IMO,
2008
, “
Report of the Marine Environment Protection Committee on its' Fifty-Eighth Session—Revised MARPOL Annex VI
,” International Maritime Organization, London, Report No.
MEPC 58/23/Add.1
.https://www.epa.gov/sites/production/files/2016-09/documents/mepc58-23-annexes13-14.pdf
3.
IMO, 2006, “
Annex VI. Regulations for the Prevention of Air Pollution From Ships and NOx Technical Code
,” International Maritime Organization, London, Report No. MARPOL 73/78.
4.
Dehaer
,
I.
,
2002
, “
Overview of NOx Emission Controls in Marine Diesel Engines
,”
Energy Sources
,
24
(
4
), pp.
319
327
.
5.
Raptotasios
,
S. I.
,
Sakellaridis
,
N. F.
,
Papagiannakis
,
R. G.
, and
Hountalas
,
D. T.
,
2015
, “
Application of a Multi-Zone Combustion Model to Investigate the NOx Reduction Potential of Two-Stroke Marine Diesel Engines Using EGR
,”
Appl. Energy
,
157
, pp.
814
823
.
6.
Caton
,
J. A.
,
2012
, “
The Thermodynamic Characteristics of High Efficiency, Internal-Combustion Engines
,”
Energy Convers. Manage.
,
58
, pp.
84
93
.
7.
Sun
,
X. X.
,
Liang
,
X. Y.
,
Shu
,
G. Q.
,
Lin
,
J. S.
,
Wang
,
Y. S.
, and
Wang
,
Y. J.
,
2017
, “
Numerical Investigation of Two-Stroke Marine Diesel Engine Emissions Using Exhaust Gas Recirculation at Different Injection Time
,”
Ocean Eng.
,
144
, pp.
90
97
.
8.
Wang
,
C.
,
Wang
,
T. Y.
,
Sun
,
K.
,
Lu
,
Z.
, and
Gui
,
Y.
,
2017
, “
Effects of EGR and Injection Strategies on the Performance and Emissions of a Two-Stroke Marine Diesel Engine
,”
SAE
Paper No. 2017-01-2249.
9.
Caiazzo
,
G.
,
Langella
,
G.
,
Miccio
,
F.
, and
Scala
,
F.
,
2013
, “
An Experimental Investigation on Seawater SO2 Scrubbing for Marine Application
,”
Environ. Prog. Sustain.
,
32
(
4
), pp.
1179
1186
.
10.
Kjølholt
,
J.
,
Aakre
,
S.
,
Jürgensen
,
C.
, and
Lauridsen
,
J.
,
2012
, “
Assessment of Possible Impacts of Scrubber Water Discharges on the Marine Environment
,” Environmental Protection Agency, Danish Ministry of the Environment, Copenhagen, Denmark, Environmental Project No.1431.
11.
Jiang
,
L. P.
,
Kronbak
,
J.
, and
Christensen
,
L. P.
,
2014
, “
The Costs and Benefits of Sulphur Reduction Measures: Sulphur Scrubbers Versus Marine Gas Oil
,”
Transp. Res. Part D Transp. Environ.
,
28
, pp.
19
27
.
12.
Panasiuk
,
I.
, and
Turkina
,
L.
,
2015
, “
The Evaluation of Investments Efficiency of SOx Scrubber Installation
,”
Transp. Res. Part D Transp. Environ.
,
40
, pp.
87
96
.
13.
Anderson
,
M.
,
Salo
,
K.
, and
Fridell
,
E.
,
2015
, “
Particle- and Gaseous Emissions From an LNG Powered Ship
,”
Environ. Sci. Technol.
,
49
(
20
), pp.
12568
12575
.
14.
Wei
,
L. J.
,
Cheng
,
R. P.
,
Mao
,
H. J.
,
Geng
,
P.
,
Zhang
,
Y. J.
, and
You
,
K.
,
2018
, “
Combustion Process and NOx Emissions of a Marine Auxiliary Diesel Engine Fuelled With Waste Cooking Oil Biodiesel Blends
,”
Energy
,
144
, pp.
73
80
.
15.
Atmanli
,
A.
,
Yüksel
,
B.
,
Ileri
,
E.
, and
Karaoglan
,
A. D.
,
2015
, “
Response Surface Methodology Based Optimization of Diesel–n-Butanol–Cotton Oil Ternary Blend Ratios to Improve Engine Performance and Exhaust Emission Characteristics
,”
Energy Convers. Manage.
,
90
, pp.
383
394
.
16.
Atmanli
,
A.
,
Ileri
,
E.
, and
Yilmaz
,
N.
,
2016
, “
Optimization of Diesel–Butanol–Vegetable Oil Blend Ratios Based on Engine Operating Parameters
,”
Energy
,
96
, pp.
569
580
.
17.
Liu
,
H. Q.
,
Lu
,
L.
, and
Wang
,
Z. J.
,
2014
, “
Evaluation Analysis of Scavenging Process of Two-Stroke Marine Diesel Engine by Experiment and Simulation
,”
J. Therm. Sci. Tech.
,
9
(
2
), pp.
1
9
.
18.
Zhou
,
S.
,
Gao
,
R. F.
,
Feng
,
Y. M.
, and
Zhu
,
Y. Q.
,
2017
, “
Evaluation of Miller Cycle and Fuel Injection Direction Strategies for Low NOx Emission in Marine Two-Stroke Engine
,”
Int. J. Hydrogen Energy
,
42
(
31
), pp.
20351
20360
.
19.
Liu
,
H. F.
,
Zhang
,
H. X.
,
Wang
,
H.
,
Zou
,
X.
, and
Yao
,
M. F.
,
2016
, “
A Numerical Study on Combustion and Emission Characteristics of Marine Engine Through Miller Cycle Coupled With EGR and Water Emulsified Fuel
,”
SAE
Paper No. 2016-01-2187.
20.
Lee
,
J.-W.
,
Baek
,
H.-M.
,
Han
,
K.-Y.
,
Rho
,
B.-S.
, and
Choi
,
J.-S.
,
2017
, “
Application of Miller Cycle for Two-Stroke Marine Diesel Engine
,”
J. Korean Soc. Mar. Eng.
,
41
(
6
), pp.
523
528
.
21.
Feng
,
L. Y.
,
Tian
,
J. P.
,
Long
,
W. Q.
,
Gong
,
W. X.
,
Du
,
B. G.
,
Li
,
D.
, and
Chen
,
L.
,
2016
, “
Decreasing NOx of a Low-Speed Two-Stroke Marine Diesel Engine by Using In-Cylinder Emission Control Measures
,”
Energies
,
9
(
4
), p.
304
.
22.
Pang
,
K. M.
,
Karvounis
,
N.
,
Walther
,
J. H.
, and
Schramm
,
J.
,
2016
, “
Numerical Investigation of Soot Formation and Oxidation Processes Under Large Two-Stroke Marine Diesel Engine-Like Conditions Using Integrated CFD-Chemical Kinetics
,”
Appl. Energy
,
169
, pp.
874
887
.
23.
Theotokatos
,
G.
,
Guan
,
C.
,
Chen
,
H.
, and
Lazakis
,
I.
,
2018
, “
Development of an Extended Mean Value Engine Model for Predicting the Marine Two-Stroke Engine Operation at Varying Settings
,”
Energy
,
143
, pp.
533
545
.
24.
Andersen
,
F. H.
,
Hult
,
J.
,
Nogenmyr
,
K.-J.
, and
Mayer
,
S.
,
2013
, “
Numerical Investigation of the Scavenging Process in Marine Two-Stroke Diesel Engines
,”
SAE
Paper No. 2013-01-2647.
25.
Karvounis
,
N.
,
Pang
,
K. M.
,
Mayer
,
S.
, and
Walther
,
J. H.
,
2018
, “
Numerical Simulation of Condensation of Sulfuric Acid and Water in a Large Two-Stroke Marine Diesel Engine
,”
Appl. Energy
,
211
, pp.
1009
1020
.
26.
Blair
,
G. P.
,
1996
,
Design and Simulation of Two-Stroke Engines
,
Society of Automotive Engineers
,
Warrendale, PA
.
27.
Amsden
,
A. A.
,
1989
, “
A Computer Program for Chemically Reactive Flows With Sprays
,” Los Alamos National Laboratory, Santa Fe, NM, Report No. LA-11560-MS.
28.
Sun
,
X. X.
,
Liang
,
X. Y.
,
Shu
,
G. Q.
,
Lin
,
J. S.
,
Wei
,
H. Q.
, and
Zhou
,
P. L.
,
2018
, “
Development of a Surrogate Fuel Mechanism for Application in Two-Stroke Marine Diesel Engine
,”
Energy
,
153
, pp.
56
64
.
29.
Beale
,
J. C.
, and
Reitz
,
R. D.
,
1999
, “
Modeling Spray Atomization With the Kelvin-Helmholtz/Rayleigh-Taylor Hybrid Model
,”
Atomization Sprays
,
9
(
6
), pp.
623
650
.
30.
Schmidt
,
D. P.
, and
Rutland
,
C. J.
,
2000
, “
A New Droplet Collision Algorithm
,”
J. Comput. Phys.
,
164
(
1
), pp.
62
80
.
31.
Cao
,
Z. Y.
,
Wang
,
T. Y.
,
Sun
,
K.
,
Cui
,
L.
, and
Lu
,
Z.
,
2017
, “
Numerical Analysis of Scavenging Process in a Large Marine Two-Stroke Diesel Engine
,”
SAE
Paper No. 2017-01-2201.
32.
Sun
,
X. X.
,
Liang
,
X. Y.
,
Shu
,
G. Q.
,
Wang
,
Y. J.
,
Wang
,
Y. S.
, and
Yu
,
H. Z. N.
,
2017
, “
Effect of Different Combustion Models and Alternative Fuels on Two-Stroke Marine Diesel Engine Performance
,”
Appl. Therm. Eng.
,
115
, pp.
597
606
.
33.
Struckmeier
,
D.
,
Tsuru
,
D.
,
Kawauchi
,
S.
, and
Tajima
,
H.
,
2009
, “
Multi-Component Modeling of Evaporation, Ignition and Combustion Processes of Heavy Residual Fuel Oil
,”
SAE
Paper No. 2009-01-2677.
34.
Kontoulis
,
P.
,
Chryssakis
,
C.
, and
Kaiktsis
,
L.
,
2017
, “
DE3-1: Evaluation of Pilot Injections in a Large Two-Stroke Marine Diesel Engine, Using CFD and T-φ Mapping
,”
International Symposium on Diagnostics and Modeling of Combustion in Internal Combustion Engines,
pp.
181
188
.
35.
Sun
,
X. X.
,
Liang
,
X. Y.
,
Shu
,
G. Q.
,
Wang
,
Y. S.
,
Wang
,
Y. J.
, and
Yu
,
H. Z. N.
,
2017
, “
Development of a Reduced n-Tetradecane–Polycyclic Aromatic Hydrocarbon Mechanism for Application to Two-Stroke Marine Diesel Engines
,”
Energy Fuel
,
31
(
1
), pp.
941
952
.
36.
Wang
,
S. L.
,
Zhu
,
X. D.
,
Somers
,
L. M. T.
, and
de Goey
,
L. P. H.
,
2017
, “E
ffects of Exhaust Gas Recirculation at Various Loads on Diesel Engine Performance and Exhaust Particle Size Distribution Using Four Blends With a Research Octane Number of 70 and Diesel
,”
Energy Convers. Manage.
,
149
, pp.
918
927
.
37.
Divekar
,
P. S.
,
Chen
,
X.
,
Tjong
,
J.
, and
Zheng
,
M.
,
2016
, “
Energy Efficiency Impact of EGR on Organizing Clean Combustion in Diesel Engines
,”
Energy Convers. Manage.
,
112
, pp.
369
381
.
38.
Damodharan
,
D.
,
Sathiyagnanam
,
A. P.
,
Rana
,
D.
,
Kumar
,
B. R.
, and
Saravanan
,
S.
,
2018
, “
Combined Influence of Injection Timing and EGR on Combustion, Performance and Emissions of DI Diesel Engine Fueled With Neat Waste Plastic Oil
,”
Energy Convers. Manage.
,
161
, pp.
294
305
.
39.
Akihama
,
K.
,
Takatori
,
Y.
,
Inagaki
,
K.
,
Sasaki
,
S.
, and
Dean
,
A. M.
,
2001
, “
Mechanism of the Smokeless Rich Diesel Combustion by Reducing Temperature
,”
SAE
Paper No. 2001-01-0655.
40.
Kitamura
,
T.
,
Ito
,
T.
,
Senda
,
J.
, and
Fujimoto
,
H.
,
2002
, “
Mechanism of Smokeless Diesel Combustion With Oxygenated Fuels Based on the Dependence of the Equivalence Ratio and Temperature on Soot Particle Formation
,”
Int. J. Engine Res.
,
3
(
4
), pp.
223
248
.
41.
Kook
,
S.
,
Bae
,
C.
,
Miles
,
P. C.
,
Choi
,
D.
, and
Pickett
,
L. M.
,
2005
, “
The Influence of Charge Dilution and Injection Timing on Low Temperature Diesel Combustion and Emissions
,”
SAE
Paper No. 2005-01-3837.
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