Patent ID: 11933240
Assignee: CATERPILLAR INC.
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC F | IPC F

Claim 17:
18. A NOx control system for an internal combustion engine comprising:
a water supply conduit;
a water injector fluidly connected to the water supply conduit;
a heater coupled to the water supply conduit and structured to heat water conveyed to the water injector sufficiently for injection as steam into an intake conduit for the engine;
a sensor structured to monitor an engine parameter indicative of at least one of an exhaust NOx level or a change to an exhaust NOx level of the engine; and
a NOx control unit coupled to the sensor and in control communication with the water injector, the NOx control unit being structured to:
receive data of the monitored engine parameter produced by the sensor;
compare an exhaust NOx level indicated by the data to a target NOx level;
output a water injection command to the water injector based on a difference between the indicated exhaust NOx level and the target NOx level; and
limit the exhaust NOx level of the engine based on an injection of water as steam produced in response to the water injection command.