METHOD FOR A DIESEL ENGINE WITH SCR CATALYST (VARIANTS) Russian patent published in 2018 - IPC F01N9/00 F01N3/20 

FIELD: machine building.

SUBSTANCE: present invention relates to systems and methods for managing ammonia storage in a selective catalytic reduction catalyst. Method for engine (10) with selective catalytic reduction (SCR) catalyst (71) includes injecting ammonia by means of nozzle (125) during a final exhaust blowdown of cylinder (30) chosen for its ignition sequence, until a predetermined value of ammonia is stored in SCR catalyst (71) in response to a vehicle-off event. Nozzle (125) injects ammonia until the predetermined value of ammonia is accumulated in SCR catalyst (71) in response to a subsequent vehicle-on event when the amount of ammonia accumulated in SCR catalyst (71) is less than the predetermined value. In response to a thermal event, when a vehicle-on event does not occur, and temperature of SCR catalyst (71) is less than the upper threshold temperature, ammonia is injected by nozzle (125) until the target value of ammonia is accumulated in SCR catalyst (71). In this case, the target ammonia value is based on the amount of ammonia accumulated in SCR catalyst (71) and the temperature in SCR catalyst (71) after the thermal event. Variants of the method for a diesel engine with a selective catalytic reduction catalyst are also disclosed.

EFFECT: technical result is to reduce the delay in achieving the target ammonia storage values in the catalyst.

17 cl, 3 dwg