ACERT Technology: How Caterpillar Engines Meet Current and ...

ACERT ® Technology: How Caterpillar Engines
Meet Current and Future Emission Limits
Dr. George Lustgarten
Director Power Systems Engineering,
Caterpillar Inc.
This presentation is only a fragment of one of the most exciting stories written
by the reciprocating engine industry facing the challenge of the increasingly
stringent emission rules. It is about Caterpillar’s contribution to preserve our
environment with engines, which are cleaner and, at the same time, preserve
or increase customer value.
But first of all, let me introduce to you Caterpillar's global base for engine development:
• We develop large high-speed and medium-speed engines with speeds between
720 and 1800 rpm covering a power range between 500 and
9000 hp in our Large Engine Center in Lafayette/IN.
• Cat Fuel Systems in Pontiac Illinois is our own business - unit serving Cat
and other engines with electronically controlled advanced fuel systems, as
we have recognized the strategic importance of this technology.
• The Mossville Engine Center in Peoria/Ill is a world leader in developing
and manufacturing medium and heavy duty engines for machines, trucks
and other applications in a range of 150-600 hp.
• Smaller, compact engines known worldwide as Perkins engines between
7 and 250 hp are build in Peterborough, UK.
• The top of our power range, Caterpillar medium-speed technology, is developed
in Kiel and Rostock.
1

The global Research & Development (R&D) activity is supported by our Technical
Research Center located at Caterpillar’s headquarters in Peoria/Ill. It
supports our engineers with fundamental research on combustion, emissions,
noise, structures, advanced materials and complete power systems. Engines
are tested in over 100 cells capable to accommodate units up to 9000 hp.
Emissions have been the primary driver of engine development during the last
decade, as shown here for the Environmental Protection Agency (EPA) NOx
limits. The most restrictive on-highway limits precede only by 2 - 4 years the
land based application. NOx and particulate emissions have been dramatically
reduced and will be reduced by an additional 95 % until 2010. Eventually all
emissions will converge towards a “Near Zero Emission” situation.
Marine emission rules are lagging behind but show a downward trend as well.
They will leverage the technology developed for the on-highway application.
The pressure is increasing, not only from the regulator side who even offers
incentives for low emissions but also from the users and shipbuilder side.
They are ready to accept their environmental responsibility, want to preserve
the value of their investment and favor low NOx solutions, “Green Ships” and
invisible smoke.
The diesel industry has responded to the challenge and established a record
of continuous improvement in customer value while making our engines
cleaner.
As emission limits become more stringent, solving the value equation becomes
more difficult:
Emission reduction with conventional methods may reduce customer value,
affecting fuel efficiency, requiring complex systems, expensive aftertreatment
installations, addition of water, etc.
We, at Caterpillar, have accepted the challenge to reduce emissions but increase
customer value at the same time.
2

In 1999, Caterpillar started to fund R&D work for what would become the largest
single effort in this industry, with the following objectives:
• Meet the most stringent current emission rules
• Enhance true customer value
• Minimize pollutants where they are generated, i.e. in the combustion space
• We have also developed a technology, which serves as a stepping-stone
for meeting future regulations applying evolutionary steps.
Caterpillar has spent in this effort some $750M, and continues to spend until
“Near Zero Emissions” come true. Therefore, we have decided to leverage this
huge investment across the whole engine range, starting with the high-speed
engines used for on-highway and land based applications up to the mediumspeed
engines produced in Kiel and Rostock.
The result is what we call the ACERT ® Technology, a unique solution for emission
reduction.
It has already been successfully introduced for high-speed, heavy duty all the
way up to some 1700 hp. What makes the difference?
It is the superior system integration of key technologies:
• A hydraulically actuated, fully flexible fuel system, capable of split injections,
variable timing and able to flex in injection intensity and fuel rate.
• A high boost, single- or two-stage, very compact turbocharger arrangement
to reduce the combustion temperatures by increasing the amount of air.
• Flexible, electronically controlled valve timing combining Turbo Power with
Intelligent Valve Control optimizing fuel efficiency and emission for each
operation point.
• A low emission combustion system with intensive mixing for rapid combustion.
• As the flexibility of the system is increased, a huge number of parameters
can be now selected to change the characteristics of Fuel Systems and Air
Systems. Powerful Caterpillar electronic controls do the job.
• Finally, simple and reliable oxidation catalysts are used only as an exception
to finish the good combustion job done by the engine itself.
3

The principles applied here are similar for the medium-speed engines as you
will see later on.
The production of emission certified ACERT ® engines was started more than a
year ago. We have successfully met the stringent emission rules for mobile
and stationary applications. We have certified our product for the newly enforced
EPA emission rules (equivalent to Euro 4). We have also demonstrated
that the ACERT ® Technology is more reliable, less complex and more efficient
than the rest of the industry.
The huge investment made with ACERT ® is currently leveraged across the
whole Caterpillar product base:
• It is expanded at the lower end in the 100-250 hp range for the Perkins engines.
It is also applied for our large high-speed product up to some
5400 hp, which is going to set new standards in efficiency, power density
and reliability for marine and other land based applications.
And finally we have initiated the introduction of the ACERT ® Technology to our
medium-speed product for marine use, subject of today's presentation.
Key criteria applied were:
• Use the same synergistic system approach, instead of forcing a quantum
step in the development of a single technology.
• Combine the traditional MaK engine reliability and vast experience in HFO
operation with the best and finest of Caterpillar engine technology.
• Avoid additional cost and complexity of complicated systems such as aftertreatment
or water injection. Let the engine itself do the job to the maximum
possible extent!
4

We have defined our first and immediate goal in migrating of the ACERT ®
emission technology to the MaK engine as follows:
• Demonstrate NOx levels 30 % below the current IMO rules with advanced,
ACERT ® combustion technology without any external systems or complex
additions to the engine design but maintain the excellent fuel efficiency, a
distinguishing feature of the MaK engine.
• Achieve invisible smoke over the whole operation range, particularly important
for passenger ships and frequent operation in emission sensitive areas
such as coastal waters.
You will recognize that the key elements of medium-speed ACERT ® Technology
are very similar to their high-speed counterpart.
Superior integration continues to be the main differentiator. It combines key
technologies such as combustion, fuel injection, turbocharging, and valve control.
Our endeavor was, to quickly leverage the ACERT ® specific flexibility in the
rugged marine environment by using readily available, simple, proven and
reliable components. The enabler is called the Flex Cam Technology.
But let us highlight the key features in more detail:
1. The starting point: The combustion system benefits from the long-stroke
technology, the foundation for clean combustion and high fuel efficiency,
distinguishing feature of the MaK engine against the rest of the industry.
2. The variable injection intensity is key for good combustion and invisible
smoke at low load. It improves atomization and fuel distribution. The injection
characteristic is modified at low load by the simple and reliable eccentric
cam mechanism - the Flex Cam. As our engines are designed to burn
heavy fuels of lowest quality, we have decided to maintain - for the time being
- the robust mechanical injection, capable to deliver fuel at pressures
beyond 1600 bar. Hydraulically actuated fuel systems with equivalent capability
are under development and will be applied in a next step, as you
will hear later on.
5

3. High performance turbochargers interact with the load controlled, variable
valve timing system. This is a key enabler for low NOx emissions and rapid
engine acceleration characteristic. Again, the Flex Cam mechanism is
adapting valve opening and closing events over the engine load.
The Flex Cam control system consists, as already mentioned, of simple, rugged
components, easily adaptable to the standard engine. The pneumatically
actuated eccentric mechanism controls position between roller and fuel-, respectively
valve cams. A complete retrofit kit including the Flex Cam module,
fuel system and turbocharger components can be easily applied for engines
already in operation.
The first engine to benefit from the ACERT ® Technology is the M 43, as it offers
an attractive solution for emission sensitive applications such as ferries,
cruise ships, RoRo’s.
Goal achievement has been fully demonstrated:
• NOx emissions amount to 8 g/kWh and below, all the way down to 25 %
engine load, which is 30 % less than the current emission standard.
• Smoke remains below the visibility limit of 0,5 over the whole operation
range. Optionally, smoke can be reduced to less than 0,3 for engines meeting
the IMO NOx standards only.
Production for the ACERT ® technology has been officially released for the
M 43 C. The same feature is currently being introduced to the M 32 C.
As previously emphasized, we, at Caterpillar, aim to stay in the front league in
meeting the future emission regulations. First engine tests on MaK engines,
with expanded ACERT ® Technology, have revealed additional opportunities.
We have already run the engine with hydraulically controlled fuel systems capable
of split injections. We have demonstrated that ACERT ® multi-parameter
optimization techniques are able to reduce NOx emission by 50 % and run the
engine without any visible smoke, which is the target area for our next development
step.
6

We detain a large experience with electronically controlled, hydraulically actuated
advanced fuel systems used in small, medium and large high-speed engines.
This constitutes the solid platform from which Caterpillar plans to launch
unique fuel system designs, capable to meet the expectation of our customers
in heavy fuel operation.
The launch of an extensive field testing and validation program with what we
call the Single Fluid Hydraulically Controlled Fuel System is already underway.
I am reaching the conclusion:
The application of ACERT ® Technology across the whole Caterpillar engine
base has offered a unique opportunity to strengthen the position of the reciprocating
engine, a technology invented more than 100 years ago. Power density
has demonstrated quantum steps without affecting reliability. Efficiency is unparalleled.
All this happened under the pressure of economics.
Superior system integration, or what we have defined as ACERT ® Technology
adds a new dimension. It has resolved the complicated balance between superior
customer value and low emissions.
It has made Caterpillar marine medium-speed engines ready to accept the
current and future challenge of emission standards without or with little additional
complexity. Which is, so we do believe, in the best interest of our customers
in the marine industry.
7

Cat Fuel Systems
Pontiac Ill
Large Engine Center
Lafayette IN
500-9000 hp
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Global Base for Engine Development
Med. & Heavy Duty
High-Speed
Peoria, Ill
Greenville NC
150-600 hp
Compact Engines
Peterborough, UK
7-250 hp
Medium-Speed
Kiel & Rostock, D
1000-22000 hp

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Emission Rules: The Main Technology Driver
N0 x (g/hp*hr)
12
10
8
6
4
2
0
IMO I
IMO II
1980 1985 1990 1995 2000 2005 2010 2015

Customer Value
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The Challenge
Customer
Expectations
We must
maintain
customer value
Emissions
Future
regulations
challenge the
value equation
History

Flexible Fuel Systems
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Superior System Integration
ACERT ® Technology for Heavy Duty Engines
Combustion
Controls
Aftertreatment
Advanced Turbocharging
Variable Valve
Timing

Leveraging ACERT ® Technology to Marine Engines
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� Use the ACERT ® System Approach
� Maintain MaK Engine Reliability in Heavy Fuel Operation
� Avoid Additional Cost Complexity of Aftertreatment Systems
(SCR, Water Injection,..)

Smoke Emission (FSN)
2
1.5
1
0.5
0
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Achieve invisible
smoke over the
whole operation
range
ACERT ® Goal
Meeting Customer Expectations and Future Emission Rules
0 20 40 60 80 100
Power Output (%)
Reduce NO x to meet
local regulations and
future IMO rules
-30%
20
15
10
5
0
NOx Emission (g/kWh)

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ACERT ® Making a Difference
Superior System Integration with Flex Cam
Technology
Long Stroke
Technology
Variable Injection
Intensity
FCT Control
The Medium
Speed ACERT
SCR only Optional
High Performance
Turbo
Variable Valve
Timing

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The Starting Point for ACERT ®
The MaK Engine is built upon the Long-Stroke Technology
Stoke / Bore Ratio (-)
1,8
1,6
1,4
1,2
1,0
M 20 M 25 M 32
M 43
MaK
Others
150 250 350 450 550
Bore (mm)
MaK engines have a long stroke
design which is leading the field

Introducing ACERT ® Fuel System Flexibility
for Medium-Speed Engines running on HFO
Requirements for
Low Smoke
Emission:
� High Injection
Pressure Capability
(> 1600 bar)
� High Injection
Intensity at Low
Load
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Introducing ACERT ® Technology to Air Systems
for Medium-Speed Engines, running on HFO
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Variable inlet valve event for NO x Reduction
Variable exhaust valve event for better load pick up

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ACERT ®
The Elements of the FCT System

Smoke- Emission (FSN)
2,5
2,0
1,5
1,0
0,5
0,0
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ACERT ® For M 43 C
Smokeless Operation with reduced NO x Emissions
Switch Point
0 25 50 75 100
Power Output (%)
Smoke
NO x
15
12
9
6
3
0
NOx - Emission (g/kWh)

max. Smoke Emission (FSN)
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2
1,5
1
0,5
0
Invisible Smoke
ACERT ® Roadmap
Prepared to Meet Future Emission Regulations
SFH
Step 2
Target Area
IMO II
Low NOx
0 2 4 6 8 10 12 14
NOx Emission Cycle Value (g/kWh)
FCT
IMO I
Low Smoke
IMO

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The new VM 43 C ACERT® with
� Smokeless operation
Flex Cam Technology
� Ready for IMO II NO x Emission Standards
� Proven Technology
� Lowest Complexity
� Retrofit Capability