CIMAC Congress - Schiff & Hafen

Monday, 14 June
Tuesday, 15 June
Thursday, 17 June
Wednesday, 16 June
container feeder running on HFO 380, various components were
dismantled and inspected. The components inspected included
cylinder heads, inlet and exhaust valves, main and big end bearings,
cylinder liners and landing surfaces, pistons, cams and rollers.
Except for the cylinder liners, the named components are part of the
manufacturer’s recommendations for a 30,000 hour overhaul.The
cylinder heads were found in excellent overall condition, showing
the expected light soiling in the combustion chamber. All hydraulic
nuts, exhaust gas flanges/clamps and plug-in connections for cooling
water could be dismantled without difficulty. All seals were in
excellent condition. All measurements on the valve guides were
found within tolerances. Inlet and exhaust valves were found in very
good condition with slight to moderate soiling of the stems. The
seat surfaces were fully intact and only a minimal material loss due
to high temp. corrosion could be observed on the bottom of the
exhaust valve plate. On the pistons, the combustion bowl was very
clean with a clearly visible, cleanly limited injection pattern, but no
measurable burn-off. The piston ring group was very clean overall
and no measurable wear of the chromium layer was found. The
wear of ring grooves during last 15,000 hours was measured at <
0.01mm/1,000 operating hours. Together with the piston skirts
where no irregularities were found as well, the piston crowns were
reinstalled in as-is condition. On the complete surface of the liner
the honing ridges were still present, no other wear marks such as
coke abrasion etc. found. In the upper area wear rates < 0.01mm/1,000
operating hours were measured. On one cylinder, the landing
surface of the liner to the crankcase was inspected and no traces of
relative movement between landing surface of cylinder liner and
crankcase were found. All big end and main bearings were found
with very good condition of the running surfaces with scarcely
visible, even running pattern. No cavitation marks were found, no
wear marks on the back of the bearings. The valve cams and rollers
show the known wear patterns, but no ridges are perceptible. The
running pattern is stable compared to earlier inspections. One
complete rocking lever (lower valve drive) was dismantled and
taken apart in the workshop. The check of roller, bush and pin
revealed no irregularities. All inspected components safely reached
the manufacturer’s expected lifetimes. Valves and bearings were
exchanged because a safe operation until the next scheduled
overhaul could not be guaranteed. All other inspected components
could be refitted after cleaning.
8:30 June 16th Room Scene GH
(2–1) Fundamental Engineering – Piston Engines
HERCULES-B: The continuation of a major
R&D effort towards the next generation
marine diesel engines
N. Kyrtatos, NTUA, Greece,
L. Hellberg, Wärtsilä Corp., Finland,
C. Poensgen, MAN Diesel & Turbo SE, Germany
HERCULES-Beta is the second phase of the HERCULES programme,
which was conceived in 2002 as a long-term strategic R&D plan. The
project was initiated by Europe’s two major engine manufacturers,
Wärtsilä Corporation and MAN Diesel and is jointly coordinated by
ULEME EEIG. HERCULES-Beta began on September 2008 with a
budget of EUR 25 million and it is planned to run for 36 months.
The project consortium has 32 participants, including enginecomponent
suppliers, equipment manufacturers, universities,
research institutions and shipping companies from ten European
countries. HERCULES-Beta comprises 56 subprojects and is funded
by the European Commission’s Framework Program 7 for R&D
(FP7, Theme Transport). The project’s principal aim is to reduce
marine diesel engine fuel consumption by 10% and to improve the
efficiency of marine diesel propulsion systems to more than 60%,
significantly reducing CO 2
emissions as a result. A further aim of the
project is to target ultra-low exhaust emissions by eliminating 70%
of NOx and 50% of particulates from marine engines by 2020. The
first phase of the HERCULES project concentrated on the
development of tools (e.g., simulation software, measurement
techniques, etc.) and the general investigation of potential avenues
for reducing emissions and fuel consumption. Initially, the project
established and operated prototypes. The results stemming from
this indicate a great potential for significantly reducing fuel
consumption and emissions and reaching the project’s ambitious
targets. HERCULES-Beta directly builds on the findings of the first
phase of the HERCULES project. The tools previously established
are employed to more closely investigate, understand and ultimately
optimise the engines. Both analytical investigations as well as
prototypes will be refined, based on first-phase results, with the
intention of achieving the ultra-low emission and fuel consumption
targets. Finally, by carrying out fieldtests on the prototypes developed
in the first phase, information on the important effect of real-life
boundary conditions will be gathered and analysed. The paper
presents the complex structure of the project, as well as some initial
results.
Optical and numerical investigation of the
combustion process in a single cylinder
medium speed diesel engine
U. Waldenmaier, J. Metzger, P. Porten, G. Stiesch,
MAN Diesel & Turbo SE, Germany,
T. Heidenreich, U. Wagner, Institute for
Reciprocating Engines (IFKM), University of
Karlsruhe, Germany
Strict emission regulations and the need of higher efficiency of
future diesel engines require an optimized combustion process. For
getting a better understanding of the combustion process optical
investigations represent a powerful tool and they are already widely
used within the development process of passenger car and truck
engines. For medium speed diesel engines however, optical
investigations are still not common due to costs of optical test
engines and technical practicability. Within the IP-Hercules Β project
MAN Diesel SE in cooperation with the “Institut fuer
Kolbenmaschinen” (IfKM) at the Technical University of Karlsruhe
realized optical in-situ investigations of the combustion process on
an MAN Diesel SE 32/44 CR single cylinder medium speed diesel
engine. For the optical investigations a special optical cylinder head
was developed with several optical accesses for an endoscope and
also laser illumination. Endoscopic investigations were chosen
because an emphasis was placed on minimum modifications to the
combustion chamber. The deflection of spray and combustion due
to the optical instrumentation had to be minimized in order to
obtain results fully representative of the standard engine as well. The
first optical investigations aimed on soot luminescence. For that
purpose special injectors were designed for separating a single flame
plume and spray cone respectively. Pressure and temperature
conditions at start of injection were adjusted by modified charge air
conditions. Different marine fuels were used for the tests. The images
of the combustion process were recorded with an endoscope and a
high speed camera. For comparing optical images and CFD
combustion simulation results, selected engine operating points
were simulated with a modified version of the CFD code KIVA3V-
Release2 containing additional sub-models developed both at the
Engine Research Center of the University of Wisconsin - Madison
(ERC) and at MAN Diesel. The purpose of the comparison was to
validate the CFD models with in-situ measurements inside the
No. 3 | 2010 | Ship & Offshore
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