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

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.
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