Authors
P. O. Witze, S.P. Huff, J.E. Storey, B.H. West
Publication
SAE Paper 2005-01-0186, Society of Automotive Engineers, 2005
Abstract
Laser-induced incandescence is used to measure timeresolved
diesel particulate emissions for two lean NOx
trap regeneration strategies that utilize intake throttling
and in-cylinder fuel enrichment. The results show that
when the main injection event is increased in duration
and delayed 13 crank-angle degrees, particulate emissions
are very high. For a repetitive pattern of 3 seconds
of rich regeneration followed by 27 seconds of NOx-trap
loading, we find a monotonic increase in particulate
emissions during the loading intervals that approaches
twice the initial baseline particulate level after 1000 seconds.
In contrast, particulate emissions during the regeneration
intervals are constant throughout the test
sequence.
For regeneration using an additional late injection event
(post-injection), particulate emissions are about twice
the baseline level for the first regeneration interval, but
then decay with an exponential-like behavior over the
repetitive test sequence, eventually reaching a level that
is comparable to the baseline. In contrast, particulate
emissions between regenerations decrease slowly
throughout the test sequence, reaching a level 12 percent
below the starting baseline value.
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