An Active Regeneration Aid as a Key Element for Safe Particulate Trap Use

The paper reports on the development of cost effective active regeneration aids as a “worst case solution” for implementation in diesel particulate traps, particularly with respect to long time vehicle operation in the inner-city at very low exhaust gas temperature level.

Two different principles of active measures were investigated: heating the entire exhaust gas by fuel burner to initiate the soot burning or applying so called “hot spot” heating by electrical heaters to start the regeneration of the loaded trap. Both methods may be combined with engine management measures to lower the necessary energy input.

Based on this investigation, several systems have been developed and tested on modern diesel engines for passenger cars at steady state and dynamic operation at difficult conditions such as low speed and very low load close to idle. Advantages and disadvantages of the systems are reported.