Methods and systems for adjusting exhaust gas flow through an aftertreatment device

Patent metadata

Field	Value
Publication number	US-10947883-B2
Application number	US-201916286452-A
Country	US
Kind code	B2
Filing date	Feb 26, 2019
Priority date	Mar 6, 2018
Publication date	Mar 16, 2021
Grant date	Mar 16, 2021

Abstract

Methods and systems are provided for a flow device shaped to adjust flow to radial positions of an emission control device. In one example, a system may include where the flow device comprises a plurality of inner openings that align while a plurality of outer openings are misaligned to flow exhaust gas proximal to a central axis of an exhaust passage, and where the plurality of outer openings are aligned and the plurality of inner openings are misaligned to flow exhaust gas distal to the central axis.

First claim

The invention claimed is:

1. A system comprising:
a flow device shaped to flow exhaust gas to an outer region or an inner region of an emission control device, wherein the flow device comprises a rotatable first plate and a fixed second plate, each of the first plate and the second plate comprising inner and outer openings, wherein an alignment of the inner and outer openings is adjusted via a rotation of the first plate;
a temperature sensor and a volumetric flow sensor arranged upstream of the emission control device; and
a controller with computer-readable instructions stored on non-transitory memory thereof that when executed enable the controller to:
adjust the flow device in response to a comparison of a temperature sensed by the temperature sensor to a threshold temperature and a comparison of a volumetric exhaust gas flow sensed by the volumetric flow sensor relative to a threshold value.

2. The system of claim 1 , wherein the outer openings are misaligned and the inner openings are aligned in a first working position of the flow device, wherein the outer openings are blocked from flowing exhaust gas therethrough.

3. The system of claim 2 , wherein the inner openings are misaligned and the outer openings are aligned in a second working position of the flow device, wherein the inner openings are blocked from flowing exhaust gas therethrough.

4. The system of claim 1 , wherein the emission control device comprises a lean NO x trap fluidly coupled to the inner openings and an oxidation catalyst fluidly coupled to the outer openings, and where the lean NO x trap is fluidly separated from the oxidation catalyst.

5. The system of claim 4 , wherein the oxidation catalyst is radially outside of and surrounds the lean NO x trap, wherein the oxidation catalyst and the lean NO x trap are concentric about a central axis of an exhaust passage.

6. A engine system comprising:
an engine fluidly coupled to an exhaust passage;
a flow device arranged along the exhaust passage comprising a first plate and a second plate, wherein one of the first plate or the second plate is rotatable between first and second positions, the first position aligning inner openings and misaligning outer openings of the first and second plates to flow exhaust gas along a central axis of the exhaust passage, the second position aligning outer openings and misaligning inner openings of the first and second plates to flow exhaust gas away from the central axis of the exhaust passage;
a catalytic converter device comprising an LNT arranged along an inner region of the catalytic converter device and an oxidation catalyst arranged along an outer region of the catalytic converter device, wherein only the LNT receives exhaust gas when the flow device is in the first position and only the oxidation catalyst receives exhaust gas when the flow device is in the second position;
a temperature sensor arranged upstream of the catalytic converter configured to sense a temperature of exhaust gas;
a volumetric sensor arranged upstream of the catalytic converter configured to sense a volumetric flow of exhaust gas; and
a controller with computer-readable instructions stored on non-transitory memory thereof that when executed enable the controller to:
rotate one of the first or second plates to the first position in response to the temperature of exhaust gas being less than a threshold temperature and the volumetric flow of exhaust gas being less than a threshold value; and
rotate one of the first or second plates to the second position in response to one of the temperature of exhaust gas being greater than or equal to the threshold temperature or the volumetric flow of exhaust gas being greater than or equal to the threshold value.

7. The engine system of claim 6 , wherein the first plate is identical to the second plate in size and shape.

8. The engine system of claim 6 , wherein the first plate comprises a plurality of first plate inner openings and a plurality of first plate outer openings, the plurality of first plate outer openings arranged radially outside of the plurality of first plate inner openings, wherein the plurality of first plate inner openings are spaced apart from one another via radially interior surfaces of the first plate, and where the plurality of first plate outer openings are spaced apart from one another via radially outer surfaces of the first plate.

9. The engine system of claim 8 , wherein the second plate comprises a plurality of second plate inner openings and a plurality of second plate outer openings, the plurality of second plate outer openings arranged radially outside of the plurality of second plate inner openings, wherein the plurality of second plate inner openings are spaced apart from one another via radially interior surfaces of the second plate, and where the plurality of second plate outer openings are spaced apart from one another via radially outer surfaces of the second plate.

10. The engine system of claim 9 , wherein the plurality of first plate inner openings are aligned with the plurality of second plate inner openings in the first position, wherein the first position further comprises the plurality of first plate outer openings being misaligned with the plurality of second plate outer openings, the plurality of first plate outer openings blocked by radially outer surfaces of the second plate and the plurality of second plate outer openings blocked by radially outer surfaces of the first plate.

11. The engine system of claim 9 , wherein the plurality of first plate outer openings are aligned with the plurality of second plate outer openings in the second position, wherein the second position further comprises the plurality of first plate inner openings being misaligned with the plurality of second plate inner openings, the plurality of first plate inner openings being blocked by radially interior surfaces of the second plate and the plurality of second plate inner openings being blocked by radially interior surfaces of the first plate.

12. The engine system of claim 6 , wherein the first position comprises flowing exhaust gas to only the LNT of the catalytic converter without flowing exhaust gas to the oxidation catalyst of the catalytic converter, wherein the second position comprises flowing exhaust gas to only the oxidation catalyst of the catalytic converter without flowing exhaust gas to the LNT of the catalytic converter.

13. The engine system of claim 6 , wherein the catalytic converter is a first catalytic converter arranged upstream of a second catalytic converter comprising a selective reduction catalyst relative to a direction of exhaust gas flow, further comprising an injector positioned to inject directly into a portion of the exhaust passage between the first catalytic converter and the second catalytic converter.

14. The engine system of claim 13 , wherein the temperature sensor is a first temperature sensor, further comprising a second temperature sensor arranged between the first catalytic converter and the second catalytic converter, wherein the temperature sensed by the first temperature sensor is compared to a first threshold temperature and a temperature sensed by the second temperature sensor is compared to a second threshold temperature, wherein the injector injects in response to the temperature sensed by the second temperature sensor being greater than the second threshold temperature.

15. A method comprising:
via a controller with computer-readable instructions stored on non-transitory memory thereof:
rotating a first plate relative to a fixed second plate of a flow device arranged upstream

Assignees

• Ford Global Tech Llc

Inventors

• Goebel Felix
• Grosch Guenter
• Lach Rainer
• Fritsche Richard

Classifications

• F01N3/208

  Control of selective catalytic reduction [SCR], e.g. by adjusting the dosing of reducing agent · CPC title

• F01N2900/1404

  Exhaust gas temperature · CPC title

• F01N2610/02

  the substance being ammonia or urea · CPC title

• F01N2290/00

  Movable parts or members in exhaust systems for other than for control purposes · CPC title

• F01N3/103

  Oxidation catalysts for HC and CO only · CPC title