Experimental Investigation on the Hydrogen Peroxide Fumigation Into the Inlet Duct of a Diesel Engine
Paper i proceeding, 2000
Believed to have a potential in reducing the NOx
emission level, hydrogen peroxide was fumigated into the
inlet duct of the AVL single cylinder research engine via a
standard gasoline injector, normally used in the Volvo
850-car engine. A small metallic sphere installed 3 cm
downstream the injector tip, improved the spray formation
and the uniform distribution of the fumigated peroxide
fluid upstream the intake valve. The hydrogen peroxide
flow was varied according to the desired value via an
electronic pulse frequency generator.
The engine, equipped with an electronic unit injector, was
initially run without any fumigation fluid until the
specifications of the engine test point were reached and
remained very stable. Further, the hydrogen peroxide
injection was activated with three different injection flows,
and the engine performance, including emission levels,
was compared to reference performance. To avoid
secondary effects on combustion processes and
emission levels, the engine was run with the same fuel/air
ratio.
The most expected effect of the hydrogen peroxide
fumigation would be on the NOx emission reduction.
However, it was observed that other emissions such as
CO and HC were remarkably affected as well.
Experimental results have shown that the hydrogen
peroxide fumigation affects the engine thermochemistry,
but not necessarily the fuel consumption and other
energetic parameters of the engine. However, the
increase of the fumigation flow above a certain limit could
deteriorate the combustion quality, thereby increase HC,
CO and soot formation levels.
Nevertheless, heat release and ignition delay, (evaluated
according to the “Dragon” software program and
acquisition from “Burst to File” PC based sampling
system)[1], [3] show that the optimal fumigated flow of the
hydrogen peroxide might reduce the ignition delay, and
thereby significantly improve the engine thermochemistry
output.
Verified effective possibilities for using hydrogen peroxide
fumigation, would lead to a proper version of the intake
manifold design, which would bring to another solution for
low emission level diesel engines