Volvo D13J, Руководство водителя

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38 VOLVO Engines
New stringent standards for exhaust emission control begin with the US 2010 engine model
year. The Diesel Particulate Filter (DPF) system has been developed to act in combination
with ultra low sulphur diesel (ULSD) fuel to reduce particulate emissions to meet the
requirement. The Exhaust After-Treatment System (EATS) includes all the engine and
exhaust emissions control components that are required to meet the stringent US 2010
standard.
Particulate matter consists of soot and ash in the exhaust that engines with an EGR system
alone, are not equipped to handle. The particulate matter is considered a contaminant that
contains undesirable elements. The DPF system reduces the unwanted elements to a more
acceptable level defined in the regulations. There are multiple methods of reducing these
emissions. VOLVO has selected to use a Diesel Oxidation Catalyst (DOC) with a catalyzed
diesel particulate filter. The other uses a diesel particulate filter of a different kind without a
DOC and in its place uses a combustion chamber to heat the exhaust mixture thus causing
active regeneration.
The particulate matter removed from the exhaust collects on the filter surfaces. To avoid
eventual blockage, which would increase exhaust back pressure and affect power and fuel
economy, the filter must be cleaned. The DPF is cleaned automatically. The soot breaks
down to safer substances before being released to the atmosphere. Some of the ash remains,
but takes a long time to reach the point where ash clogs the filter.
Cleaning a filter so it can continue to function is called “regeneration.” Depending on vehicle
usage, the engine utilizes a passive or parked regeneration system. Either system uses high
heat to break down the chemical properties.
In “passive regeneration,” the exhaust produces enough heat continuously to convert
the soot, with approximately 260 °C (500 °F) being required. The process is slow and
continues indefinitely. Passive regeneration is possible only in vehicle applications where
the temperature is likely to remain at or above the required temperature level, making active
regeneration unnecessary.
Parked regeneration is initiated manually by the driver when alerted by the dash. The vehicle
must be stationary to begin the regeneration, and remain stationary to complete.
The Aftertreatment DPF Regeneration system is self-monitoring. Under certain duty cycles
driver action is needed to perform a parked regeneration. When driver action is needed to
perform a parked regeneration the Aftertreatment DPF Regeneration Needed icon on the
instrument cluster flashes and the message “Parked REGEN Needed” is displayed. Initiate a
parked Aftertreatment DPF regeneration at the next stop.
WARNING
Prior to ever working on the exhaust, allow
time for the entire exhaust system to cool.
Failure to do so may result in personal
injury. Severe burns can occur.