Aftertreatment heat management by controlled exhaust-gas recirculation with variable co-current flow upstream of first catalyst
AssigneeFord Global Technologies, LLC
InventorsJoerg Kemmerling, Michael Forsting, Frank Wunderlich
Life of this patent
Estimating the term…
Abstract
Methods and systems are provided for an exhaust system. In one example, the exhaust system includes an aftertreatment device and a recirculation passage. A recirculation valve is positioned in the recirculation passage and configured to control an amount of recirculated exhaust gas flowing through the recirculation passage to the aftertreatment device. The exhaust system further includes a diverter valve configured to control a flow of engine exhaust gases to different portions of a catalyst of the aftertreatment device.
Claims20
A system, comprising:
- an exhaust recirculation passage configured to inject recirculated exhaust gas from downstream of an aftertreatment device to upstream of the aftertreatment device based on a direction of exhaust gas flow;
- and
- a valve configured to direct engine exhaust gas to a first portion of a first catalyst and recirculated exhaust gas to a second portion of the first catalyst of the aftertreatment device when in a cold position.
An exhaust system of an engine, comprising:
- an aftertreatment device comprising a first catalyst upstream of a second catalyst relative to a direction of exhaust gas flow;
- a diverter valve arranged in an inlet of the aftertreatment device, the diverter valve configured to move to a first position and a second position;
- a recirculation passage configured to flow exhaust gas from downstream of the aftertreatment device to the inlet of the aftertreatment device, the recirculation passage comprising a compressor upstream of a recirculation valve, and an injector downstream of the recirculation valve;
- and
- a controller with computer-readable instructions stored on memory thereof that when executed cause the controller to:
- adjust the diverter valve to the first position in response to a temperature of the first catalyst being greater than or equal to a light-off temperature;
- and
- adjust the diverter valve to the second position in response to the temperature of the first catalyst being less than the light-off temperature.
A method, comprising:
- during a first condition, adjusting a diverter valve to a first position and flowing unfiltered exhaust gas to a first portion and a second portion of a catalyst;
- and
- during a second condition, adjusting the diverter valve to a second position and flowing unfiltered exhaust gas to only the first portion of the catalyst and filtered exhaust gas to only the second portion of the catalyst.
Dependencies are inferred from the claim text.