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Today’s shipping business is faced with the
requirement to reduce fuel oil consumption
throughout the fleet’s operating profiles. Similarly,
operational reliability and vessel availability
must be ensured, maintenance costs need to
be reduced, and emissions legislation has to be
complied with.
Wärtsilä’s Intelligent Combustion Control
system (ICC) supports to achieve all these goals.
It enables the ship’s engines to operate reliably
and in accordance with their original shop test
performance. This is done automatically on board,
in real time and regardless of the fuel in use or
ambient conditions.
The ICC system automatically balances
compression and firing pressures in all cylinders,
resulting in equal exploitation of each unit and
reduced torsional vibrations of the complete
engine. The system also protects the engine
against potential manual operating errors.
The advantages of the system become even
more significant when the fuel has to be changed
while in SOX Emission Control Areas, and always
when different fuel qualities are used for cost or
availability reasons.
Compared to an engine where the Fuel
Quality Setting (FQS) is not adjusted properly, the
measured reduction in fuel oil consumption with
an activated ICC is up to 2.5 g/kWh over the whole
engine load range. When ICC is active the specific
fuel oil consumption is reduced which results in a
decrease of CO2 emissions.
ICC benefIts • Optimized fuel consumption over whole load
range
• Reduced maintenance costs and downtime
• Fully automated balancing
• Real-time data
• Reduced workload for crew and technical
department
• Maximized availability and reliability through a
safer, finely balanced engine operation
INTELLIGENT COMBUSTION CONTROL FOR WÄRTSILÄ TWO-STROKE RT-flex ENGINES
a WeCs-9520 optIonThe ICC system is an optional part of WECS-
9520 (Wärtsilä Engine Control System),
which adjusts the peak fi ring pressure of the
engine according to the given design criteria.
The fi ring and compression pressures of
all cylinders are balanced by adjusting the
injection timing and exhaust valve closing
within their allowed operating range. All
modifi cations of engine control parameters
made in the ICC system are compliant with
the vessel’s IMO certifi cate.
The ICC system also limits the pressure
rise (compression/ combustion ratio) of the
engine as an included safety function. This
reduces the wear of engine components,
minimizes the risk of overloads, and helps
to avoid manual adjustment fl aws in case of
open loop control.
Thanks to the ICC system, the engine is
always operated according to its design criteria,
as safely and as effi ciently as possible.
InstallatIon referenCeAfter the completion of rigorous testing,
the ICC system was installed on two
vessels powered by Wärtsilä 7RT-fl ex96C
and 12RT-fl ex96C engines. The complete
installation took place during port time, and
the ICC system was commissioned during
a short voyage between European ports
without infl uencing the vessel’s schedule.
Commissioning included functionality and
performance testing.
0
25
50
75
125
100
60 70 80 90 100 110
Load
[%]
Speed [%]
operating range of ICC
30 40 50 60 70 80
SFO
C [g
/kW
h]
Load [%]
SFOC measurements on board
OPEN LOOP (FQS=0)
CLOSED LOOP (ICC)
figure 1: sfoC measurement on board.
80
90
100
110
120
130
140
30 40 50 60 70 80
P_M
AX
[bar
]
Load [%]
ISO corrected Firing Pressure
OPEN LOOP (FQS=0)
CLOSED LOOP (ICC)
figure 2: Iso corrected fi ring pressure.the compression and fi ring pressures are adjusted with ICC for each engine speed / load operating point.
62
62,5
63
63,5
64
64,5
65
65,5
66
0 20 40 60 80 100 120Compression Pressure Cyl. 1 Compression Pressure Cyl. 2 Compression Pressure Cyl. 3Compression Pressure Cyl. 4 Compression Pressure Cyl. 5 Compression Pressure Cyl. 6Compression Pressure Cyl. 7 Compression Pressure Average
-COMPRESSION PRESSURE CLOSED LOOP CONTROL ON
Com
pres
sion
Pre
ssur
e (b
ar)
time (sec)62
62,5
63
63,5
64
64,5
65
65,5
66
0 20 40 60 80 100 120Compression Pressure Cyl. 1 Compression Pressure Cyl. 2 Compression Pressure Cyl. 3Compression Pressure Cyl. 4 Compression Pressure Cyl. 5 Compression Pressure Cyl. 6Compression Pressure Cyl. 7 Compression Pressure Average
COMPRESSION PRESSURE - OPEN LOOP CONTROL
Com
pres
sion
Pre
ssur
e (b
ar)
time (sec)
Closed Loop control OFF Closed Loop control ON
Average of Pcomp
92
94
96
102
104
0 20 40 60 80 100 120Firing Pressure Cyl. 1 Firing Pressure Cyl. 2 Firing Pressure Cyl. 3Firing Pressure Cyl. 4 Firing Pressure Cyl. 5 Firing Pressure Cyl. 6Firing Pressure Cyl. 7 Firing Pressure Average Firing Pressure Setpoint
time (sec)
-FIRING PRESSURE CLOSED LOOP CONTROL
92
94
96
98
100
102
104
0 20 40 60 80 100 120Firing Pressure Cyl. 1 Firing Pressure Cyl. 2 Firing Pressure Cyl. 3Firing Pressure Cyl. 4 Firing Pressure Cyl. 5 Firing Pressure Cyl. 6Firing Pressure Cyl. 7 Firing Pressure Average Firing Pressure Setpoint
-FIRING PRESSURE OPEN LOOP CONTROL
Firi
ng P
ress
ure
(bar
)
time (sec)
Closed Loop control OFF Closed Loop control ON
Cyl. average PMax
Setpoint
figure 3: activation of ICC (Wärtsilä 7rt-fl ex96C).Compression and fi ring pressure deviations between cylinders are clearly reduced.
Compared to the original setting with
standard Open Loop Control and FQS=0, a
fuel oil consumption reduction was observed
for each operating point (fi gure 1). This was
achieved mainly with the adjustment to
the permitted peak fi ring pressure at each
speed / load point with activated Closed
Loop Control (fi gure 2).
the WärtsIlä ICC solutIon provIdes safer operatIon WIth reduCed CostsOptimized engine operation
• Fuel savings up to 2.5 g/kWh
• Automated FQS setting
Balanced mechanical and thermal load
distribution
• Automated adjustment of compression and
firing pressures
• Reduced wear and ageing of sensitive
engine components
• Prevention of mechanical and thermal
overload (high-peak pressures)
• Avoidance of unfavourable manual FQS
adjustment
ConClusIonICC ensures that the engine is operated
according to its design criteria, as safely and
as efficiently as possible. The reduction in fuel
oil consumption with an activated ICC is up to
2.5 g/kWh over the whole engine load range.
The equal exploitation of each cylinder unit of
the engine by the balancing of compression
and firing pressure reduces potential
overload and abnormal wear rates of engine
components. The ICC system helps to reduce
the work load of the crew as all adaptations
and adjustments are done automatically while
also considering fuel quality and ambient
conditions.
WARTSILA.COM
WÄRTSILÄ® is a registered trademark. Copyright © 2011 Wärtsilä Corporation. Specifications are subject to change without prior notice.