Systems and methods for a valve in a dual-core EGR cooler

Patent metadata

Field	Value
Publication number	US-11352986-B2
Application number	US-202017074479-A
Country	US
Kind code	B2
Filing date	Oct 19, 2020
Priority date	Oct 19, 2020
Publication date	Jun 7, 2022
Grant date	Jun 7, 2022

Abstract

Methods and systems are provided for directing the flow of recirculated exhaust gas (EGR) delivered to an EGR cooler. In one example, a method includes flowing EGR through an EGR cooler positioned in an EGR passage, the EGR cooler comprising a bypass passage, a first cooler core flow path, and a second cooler core flow path, and adjusting a valve of the EGR cooler to selectively block flow of the EGR through the bypass passage, the first cooler core flow path, and the second cooler core flow path. In this way, fouling of the EGR cooler may be reduced.

First claim

The invention claimed is:

1. A method, comprising:
flowing exhaust gas recirculation (EGR) through an EGR cooler positioned in an EGR passage by opening an EGR valve positioned in the EGR passage upstream or downstream of the EGR cooler, the EGR cooler comprising a bypass passage, a first cooler core flow path, and a second cooler core flow path; and
adjusting a rotary valve of the EGR cooler to selectively block flow of the EGR through the bypass passage, the first cooler core flow path, and the second cooler core flow path, the rotary valve positioned at least partially within a housing of the EGR cooler.

2. The method of claim 1 , wherein adjusting the rotary valve of the EGR cooler to selectively block flow of the EGR through the bypass passage, the first cooler core flow path, and the second cooler core flow path comprises, responsive to a first condition,
adjusting the rotary valve into a first position where the first cooler core flow path and the second cooler core flow path are each blocked; and
flowing the EGR through the bypass passage and not through the first cooler core flow path or the second cooler core flow path.

3. The method of claim 1 , wherein adjusting the rotary valve of the EGR cooler to selectively block flow of the EGR through the bypass passage, the first cooler core flow path, and the second cooler core flow path comprises, responsive to a second condition,
adjusting the rotary valve into a second position where the second cooler core flow path and the bypass passage are each blocked; and
flowing the EGR through the first cooler core flow path and not through the second cooler core flow path or the bypass passage.

4. The method of claim 1 , wherein adjusting the rotary valve of the EGR cooler to selectively block flow of the EGR through the bypass passage, the first cooler core flow path, and the second cooler core flow path comprises, responsive to a third condition,
adjusting the rotary valve into a third position where the bypass passage is blocked; and
flowing the EGR through the first cooler core flow path and the second cooler core flow path and not through the bypass passage.

5. The method of claim 1 , wherein adjusting the rotary valve of the EGR cooler to selectively block flow of the EGR through the bypass passage, the first cooler core flow path, and the second cooler core flow path comprises, responsive to a fourth condition,
adjusting the rotary valve into a fourth position where the first cooler core flow path is blocked; and
flowing the EGR through the second cooler core flow path and the bypass passage and not through the first cooler core flow path.

6. The method of claim 1 , wherein the rotary valve includes a first end plate and a second end plate coupled via a shaft, and wherein adjusting the rotary valve of the EGR cooler to selectively block flow of the EGR through the bypass passage, the first cooler core flow path, and the second cooler core flow path comprises activating a motor coupled to the shaft to rotate the shaft, the first end plate, and the second end plate.

7. The method of claim 1 , wherein the first cooler core flow path comprises a first cooler core of the EGR cooler and the second cooler core flow path comprises a second cooler core of the EGR cooler; and
wherein adjusting the rotary valve of the EGR cooler to selectively block flow of the EGR through the bypass passage, the first cooler core flow path, and the second cooler core flow path comprises adjusting the rotary valve of the EGR cooler to selectively block flow of the EGR through the bypass passage, the first cooler core, and the second cooler core.

8. A method for an engine system including an exhaust gas recirculation (EGR) cooler, comprising:
during low EGR flow conditions where EGR cooling is demanded, directing EGR through only a first cooler core flow path of the EGR cooler and not through a second cooler core flow path of the EGR cooler, via a valve in a first position; and
during high EGR flow conditions, directing EGR through both the first cooler core flow path and the second cooler core flow path, via the valve in a second position,
where the valve, in the first position, seals the second cooler core flow path at both an upstream end and a downstream end of the second cooler core flow path.

9. The method of claim 8 , further comprising during low EGR flow conditions where EGR cooling is not demanded, directing EGR through a bypass passage of the EGR cooler and not through the first cooler core flow path or the second cooler core flow path, via the valve in a third position.

10. The method of claim 9 , further comprising during low differential pressure conditions, directing EGR through both the bypass passage and the second cooler core flow path and not through the first cooler core flow path, via the valve in a fourth position.

11. The method of claim 10 , wherein the valve is a rotary valve positioned at least partially within a housing of the EGR cooler, and further comprising moving the rotary valve to the first position, the second position, the third position, and/or the fourth position by rotating a motor-driven shaft coupling a first end plate of the rotary valve to a second end plate of the rotary valve.

12. The method of claim 11 , wherein the first cooler core flow path comprises a flow path through a first cooler core of the EGR cooler and the second cooler core flow path comprises a flow path through a second cooler core of the EGR cooler, wherein the rotary valve, in the first position, seals the second cooler core at both the upstream end and the downstream end of the second cooler core by positioning a first poppet valve of the first end plate in face-sharing contact with an outlet of the second cooler core and a second poppet valve of the second end plate in face-sharing contact with an inlet of the second cooler core, wherein the first end plate further includes a first opening and the second end plate further includes a second opening, and in the first position of the rotary valve, the first opening is aligned with an outlet of the first cooler core and the second opening is aligned with an inlet of the first cooler core.

13. The method of claim 11 , further comprising adjusting an amount of EGR flowing into the EGR cooler by adjusting an EGR valve positioned upstream or downstream of the EGR cooler, and wherein the low flow EGR conditions include engine load being below a threshold load and wherein the high flow EGR conditions include engine load being above the threshold load.

14. A system, comprising:
an exhaust gas recirculation (EGR) cooler positioned in an EGR passage coupled between an exhaust manifold and an intake manifold of an engine, the EGR cooler including:
a housing;
a first cooler core;
a second cooler core;
a bypass passage, each of the first cooler core, the second cooler core, the bypass passage positioned in the housing; and
a rotary valve at least partially positioned in the housing, the rotary valve including a first end plate positioned in an outlet chamber of the EGR cooler and a second end plate positioned in an intake chamber of the EGR cooler, the first end plate and second end plate coupled to a motor via a common shaft and movable, via the motor, to four positions in order to block or allow flow of EGR through the first cooler core, the second cooler core, and the bypass passage.

15. The system of claim 14 , wherein each of the first cooler core and the second cooler core includes a plurality of gas-flowing passages in thermal contact with a heat-transfer medium.

16. The system of claim 14 , wherein

Assignees

• Ford Global Tech Llc

Inventors

• Mcconville Gregory
• Styles Daniel Joseph

Classifications

• F02M26/29

  Constructional details of the coolers, e.g. pipes, plates, ribs, insulation or materials · CPC title

• F02M26/24

  with two or more coolers · CPC title

• F02M26/23 Primary

  Layout, e.g. schematics · CPC title

• F28D7/0083

  with units having particular arrangement relative to a supplementary heat exchange medium, e.g. with interleaved units or with adjacent units arranged in common flow of supplementary heat exchange medium · CPC title

• F02M26/33 Primary

  controlling the temperature of the recirculated gases · CPC title