ELECTRIC HEATING ASSISTED PASSIVE AND ACTIVE REGENERATION FOR EFFICIENT EMISSION CONTROLS OF DIESEL ENGINES

摘要

A method of heating an exhaust gas in an exhaust after treatment system including a Diesel Oxidation Catalyst (DOC) and a diesel particulate filter (DPF) is provided. The method includes heating the exhaust gas to a predetermined temperature to increase N02 generation in the DOC when the DPF is not actively regenerated, and heating the exhaust gas to reduce an exhaust temperature gradient when the DPF is actively regenerated. The exhaust temperature gradient is reduced by providing more heat proximate a wall of an exhaust conduit and less heat proximate a center of the exhaust conduit.