The paper reports on the results of a joint research program performed at Rhône-Poulenc and AVL concerning a passive trap system with Cerium (Ce) as a new patented fuel additive in conjunction with an engine management control system to increase the exhaust gas temperature for initiating regeneration under practically all engine application conditions. Investigations were carried out on a 12L DI/TCI HD diesel engine which meets the US94 emission standards.
From the work done the most effective combination of the engine control measures has been established as an apprepriate solution to increase the exhaust gas temperature up to 400 deg. C. at minimum penalty with respect to emissions and fuel consumption.
Furthemore, the influence of Cerium on engine-out emissions and fuel consumption has been investigated. It could be shown that by using Cerium, the fuel consumption improves on average by about 2 percent.
Depending upon trap soot loading as well as on the availability of sufficiently high gas temperature the particulate trap can be cleaned to nearly the original porosity.