Mitigation of diesel emission fluid (def) deposition in exhaust system for engine
AssigneeCaterpillar Inc.
InventorKeith D. Hogan
Life of this patent
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Abstract
An exhaust system for an engine includes an exhaust conduit, a selective catalytic reduction (SCR) device in the exhaust conduit, and a diesel emission fluid (DEF) system. The diesel emission fluid system includes a DEF delivery controller structured to receive a condition signal indicative of a DEF deposition risk condition in the exhaust system, and to command an increased heat energy output of a preheater to preheat DEF to be admitted into the exhaust conduit, such that a temperature of the DEF is increased to a deposition-mitigation temperature. Related methodology and control logic is also disclosed.
Claims20
An exhaust system for an engine comprising:
- an exhaust conduit extending between an upstream end structured to receive exhaust produced by the engine, and a downstream end;
- a selective catalytic reduction (SCR) device positioned in the exhaust conduit;
- a diesel emission fluid (DEF) system including a DEF admission valve connected to the exhaust conduit at a location that is upstream of the SCR, a preheater, a condition sensor, and a DEF delivery controller;
- the DEF delivery controller is coupled with the preheater and with the condition sensor, and structured to:
- receive a condition signal produced by the condition sensor that is indicative of a DEF deposition risk condition in the exhaust system;
- and
- command an increased heat energy output of the preheater based on the condition signal, such that a temperature of DEF to be admitted into the exhaust conduit is increased to a deposition-mitigation temperature.
A diesel emission fluid (DEF) system comprising:
- a DEF delivery controller structured to couple with a preheater, for preheating DEF for delivery into an exhaust conduit in the exhaust system, and with a condition sensor, for monitoring a DEF deposition risk condition in the exhaust system;
- the DEF delivery controller being further structured to:
- receive a condition signal from the condition sensor indicative of a DEF deposition risk condition in the exhaust system;
- determine a deposition-mitigation temperature for DEF to be admitted into an exhaust conduit in the exhaust system, based on the condition signal;
- and
- command an increased heat energy output of the preheater, such that a temperature of the DEF to be admitted into the exhaust conduit is increased to the deposition-mitigation temperature.
A method of operating an exhaust system for an internal combustion engine comprising:
- producing a condition signal indicative of a diesel emission fluid (DEF) deposition risk in the exhaust system;
- increasing a heat energy output of a preheater for DEF in a DEF system of the exhaust system based on the condition signal;
- increasing a temperature of DEF in the DEF system to a deposition-mitigation temperature based on the increased heat energy output;
- and
- commanding admission of the DEF increased in temperature to the deposition-mitigation temperature into an exhaust conduit in the exhaust system.
Dependencies are inferred from the claim text.