Introduction
The lifetime of the new after-treatment
devices is influenced by the composition
of the lubricants. A novel,
non-destructive radiotracer technique
has been developed based on the
labelling of the different elements in
the engine oil, notably zinc &
calcium, which lead to the formation of
ash deposits in after-treatment systems
(ATS).
Measurement Principle
The technique consists of labelling one or more elements in the lubricant.
When the lubricant is burned in the combustion chamber, the residues are
transferred via exhaust gas to the ATS, where they tend to form deposits.
Using an appropriate radiation detector located close to the ATS,
one may measure the radiation produced by the deposited tracers.
This radiation is proportional to the amount of labelled elements trapped in the ATS.
