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Monday, May 13th
Tuesday, May 14th
Wednesday, May 15th
Thursday, May 16th
Combination of post-injection and cooled EGR at a
medium-speed diesel engine to comply with IMO Tier
III emission limits
Marko Pueschel, FVTR GmbH, Germany
Bert Buchholz, FVTR GmbH, Germany
Christian Fink, Universität Rostock, Germany
Carsten Rickert, Caterpillar Motoren GmbH & Co KG, Germany
Kai Ruschmeyer, Caterpillar Motoren GmbH & Co KG, Germany
With introduction of IMO Tier III in 2016 the marine diesel engine
technology faces a radical change. The IMO Tier III requires NOx reductions
of 75 % compared with the current level (IMO Tier II). In
connection with the stringent NOx reductions massive SOx reductions
will be introduced stepwise until 2015. In light of this, the potential
of EGR to fulfil the IMO Tier III NOx limits at medium-speed
marine diesel engines is systematically analysed. The targets are defined
by a NOx emissions level of 2 g/kWh, invisible smoke and
minimum fuel consumption penalty. The analyses are carried out
at a six-cylinder medium-speed test engine with 1,000 kW output at
1,000 rpm. The research engine is equipped with a cooled EGR system,
a common rail injection system and a programmable engine
control unit. The CR injectors are solenoid operated and allow multiple
injections. Systematic variations of EGR rate, injection pressure
and injection timing were carried out and the results regarding combustion
process, NOx and soot emissions as well as fuel consumption
are presented. The results show that significant EGR rates are
necessary to obtain NOx-reduction rates as required for IMO Tier III
compliance. These high EGR rates result in unwanted and unacceptable
soot emission levels even at increased injection pressures. To
reduce these soot emissions, post-injection strategies were analysed
at the medium-speed test engine. Post injection proved to be an efficient
soot reduction measure in onroad diesel engine. The effect of
different post injections on the soot emissions is shown. Based on
the results, the soot emission reduction potential of postinjections
at marine medium-speed diesel engines is outlined and the requirements
for a successful implementation of post-injection strategies
are discussed. The application of post-injections requires detailed
information on the dynamic behaviour of the common rail system
and especially on the CR injectors applied. Due to this, the dynamics
of the CR injectors in case of post-injections were established at
an injection rate analyser and the findings are discussed. The functionality
of the CR injectors at the test engine is monitored by measurements
of the current feed signal and the injection pressure at the
injector inlet. Finally, the preconditions for a successful application
of EGR at medium-speed marine diesel engines are summarised.
The use of EGR not only challenges the injection (rail pressure, post
injections), charging and the cooling system (EGR, charge air) but
also the engine control system.
Ten years after: results from the major programme
HERCULES A-B-C on marine engine R&D
Nikolaos Kyrtatos, National Technical University of Athens, Greece
Lars Hellberg, Wärtsilä Corporation, Finland
Christian Poensgen, MAN Diesel & Turbo SE, Germany
In the year 2004, the integrated project HERCULES-A (Higher-
Efficiency Engine R&D on Combustion with Ultra-Low Emissions
for Ships) was initiated by the major engine makers MAN and
Wärtsilä, which together hold 90% of the world market. It was the
phase I of the HERCULES R&D programme on large engine technologies.
The HERCULES-A involved 42 industrial and university
partners, with a budget of EUR 33 million, partly funded by the
European Union. The project was broad in the coverage of the various
R&D topics and considered a range of options and technologies
in improving efficiency and reducing emissions. HERCULES-B
was phase II of the programme, from 2008 to 2011, with 32 participating
organisations and EUR 26 million budget, partly funded
by European Union. The general targets for emissions and fuel
consumption were retained in HERCULES-B. However, based on
the developed know-how and results of HERCULES-A, it was possible
to narrow the search area, to focus on potential breakthrough
research and to further develop the most promising techniques for
lower specific fuel consumption (and CO 2
emissions) and ultralow
gaseous and particulate emissions. The HERCULES-C project
(2012-2015), with 22 participant organisations and EUR 17 million
budget, is phase III of the HERCULES programme and adopts
a combinatory approach, with an extensive integration of the multitude
of new technologies identified in phase I and phase II, for
engine thermal processes optimisation, system integration, as well
as engine reliability and lifetime. This paper provides an overview
of the complex structure, as well as the main achievements of the
HERCULES R&D programme in the past ten years.
Wednesday May 15th / 08:30 – 10:00 Room D
Integrated Systems and Electronic Control
Piston Engines, Gas and Steam Turbines and Applications –
Propulsion System Integration
Benefits of propulsion integration on fuel efficiency
of marine vessels
Elias Boletis, Wärtsilä Corporation, The Netherlands
A major effort is undertaken to improve the energy efficiency of
shipping. This requires that the (engine) thermal efficiency and the
ship propulsive efficiency are addressed simultaneously. New IMO
rules are referred to the vessel environmental indices (as overall energy
efficiency per carried load and distance transported) than only
to the efficiency of individual engine types and systems. The reciprocating
engine concept seems to remain the basis for fuel energy
conversion to mechanical energy, with emphasis on fuel versatility
and the broad introduction of gas. The ship propulsion systems
(fixed or controllable pitch propellers, steerable thrusters and advanced
designs of high-efficiency potential) undergo new developments
with emphasis on high vessel propulsive efficiency and
engine compatibility. The vessel design itself is also to be adapted
to the new propelling and machine room equipment. Obviously
this integration can better be done in early ship and system design
phases. The current paper describes the impact of the propulsion
system and the propeller selection on the overall vessel efficiency
optimisation. A number of vessel cases are examined in detail:
• Large container ship applications at slow steaming/propeller selection;
• Drilling vessel application/thruster optimisation;
• Gas engine application/propeller control;
• Special vessel diesel mechanic application with two-stage gear
boxes;
• Propeller power loading on vessel performance.
The paper attempts to make a quantification of the overall benefits
of the judicious selection of propulsion characteristics and provides
guidelines for the future.
Analysis and evaluation of innovative hybrid
powertrain architectures combining gas engines and
electric propulsion for tugboats
Ioannis Vlaskos, Ricardo Deutschland GmbH, Germany
David Gagliardi, Ricardo Deutschland GmbH, Germany
Martin Spiller, Ricardo Deutschland GmbH, Germany
Kevin Thuemmler, Ricardo Deutschland GmbH, Germany
May 2013 | Schiff&Hafen | Ship&Offshore SPECIAL 47