Additive Based Regeneration Adjusted for Indian Low Load Driving Profiles 2017-26-0144

Emissions of diesel engine are considered to be harmful to health especially particulate emissions. Therefore, the introduction of diesel particulate filters (DPF) were successively forced by government due to reducing the emission limits to a level where inner engine measures are not sufficient anymore. To limit additional fuel consumption by increasing backpressure over the DPF, the collected soot has to be regenerated continuously or discrete by active regeneration. Active regeneration is usually realized by injecting additional fuel either due to the engines injection system into the combustion chamber (late post injection) or via an additional fuel injection device in the exhaust line. This enables increasing exhaust temperature and / or an exothermic reaction in the diesel oxidation catalyst (DOC) of the aftertreatment system. To realize the necessary temperature increase to regenerate the DPF, both regeneration modes require a minimum exhaust gas temperature for a conversion of the injected hydrocarbons. In regions with low load distribution this minimum temperature will not be reached sufficiently.

This paper describes the additional fuel consumption for active regeneration compared to a regeneration based on electrical heating elements in combination with a fuel borne catalyst (FBC). FBC decreases the ignition temperature for the collected soot and by this the energy input from the electrical heating elements is sufficient for a regeneration.

This paper also describes a system configuration where the heating elements are implemented in a DPF system and discusses the results of a field test vehicle with a focus on low load conditions.