Methods and systems for controlling air flow paths in an engine

Patent metadata

Field	Value
Publication number	US-10041451-B2
Application number	US-201615162443-A
Country	US
Kind code	B2
Filing date	May 23, 2016
Priority date	May 23, 2016
Publication date	Aug 7, 2018
Grant date	Aug 7, 2018

Abstract

Methods and systems are provided for controlling a temperature of gases within a heat exchanger, a ratio of gases output by the heat exchanger, and selectively charging/discharging gases from the heat exchanger to one or both of an intake system or an exhaust system. In one example, a method may include controlling operation of an energy recovery device coupled to the heat exchanger in response to engine operating conditions, and increasing or decreasing flow of exhaust gas and/or compressed intake air into the heat exchanger in response to energy recovery device output.

First claim

The invention claimed is:

1. A method, comprising:
flowing intake air through a heat exchanger and selectively to each of an intake system and an exhaust system;
flowing exhaust gas through an energy recovery device coupled with the heat exchanger, through the heat exchanger, and selectively to each of the intake and exhaust system; and
adjusting the flow of intake air and exhaust gas through the heat exchanger in response to an output of the energy recovery device.

2. The method of claim 1 , wherein flowing exhaust gas includes flowing exhaust gas directly from the energy recovery device to the heat exchanger and wherein the flow of intake air and exhaust gas do not mix within the heat exchanger.

3. The method of claim 1 , further comprising, during flowing intake air and exhaust through the heat exchanger, transferring thermal energy between the intake air and exhaust gas within the heat exchanger.

4. The method of claim 1 , further comprising adjusting a flow of coolant through the heat exchanger in response to the output of the energy recovery device.

5. The method of claim 4 , wherein adjusting the flow of coolant includes decreasing the flow of coolant through the heat exchanger as the output of the energy recovery device increases.

6. The method of claim 1 , wherein adjusting the flow of intake air and exhaust gas through the heat exchanger includes one or more of decreasing the flow of intake air through the heat exchanger as the output of the energy recovery device increases, or decreasing the flow of exhaust gas through the heat exchanger as the output of the energy recovery device increases toward a threshold energy output.

7. The method of claim 1 , further comprising estimating a temperature of exhaust gas entering the heat exchanger from the energy recovery device based on the output of the energy recovery device and one or more of a temperature of the exhaust gas in the exhaust system and engine load.

8. The method of claim 1 , further comprising operating the energy recovery device in response to one or more of an engine torque output increasing above a threshold engine torque output, and an exhaust gas temperature within the exhaust system increasing above a threshold exhaust gas temperature.

9. The method of claim 1 , further comprising not operating the energy recovery device in response to one or more of an engine torque output decreasing below a threshold engine torque output, an exhaust gas temperature within the exhaust system decreasing below a threshold exhaust gas temperature, an active particulate filter regeneration, and an engine cold start, and flowing exhaust gas through the energy recovery device, without transferring heat from the exhaust gas, and to the heat exchanger.

10. The method of claim 1 , wherein flowing intake air through the heat exchanger and selectively to each of the intake system and the exhaust system includes adjusting a first valve to adjust the flow of intake air from the heat exchanger to the intake system, upstream of a compressor, and adjusting a second valve to adjust the flow of intake air from the heat exchanger to each of a location in the exhaust system upstream of a first catalyst and a location in the exhaust system downstream of the first catalyst.

11. The method of claim 1 , wherein flowing exhaust gas through the heat exchanger and selectively to each of the intake and exhaust system includes adjusting a single valve to adjust the flow of exhaust gas to each of the intake system upstream of a compressor, the intake system downstream of the compressor, and the exhaust system upstream of a turbine.

12. A system, comprising:
a heat exchanger coupled to each of an intake system and exhaust system and including a first set of passages configured to flow intake air from the intake system and to one or more of the intake and exhaust system and a second set of passages configured to flow exhaust gases from the exhaust system and to one of the intake system and exhaust system; and
an energy recovery device integrated with the heat exchanger and fluidly coupled to each of the exhaust system and the second set of passages, where exhaust gases flow from the exhaust system, through the energy recovery device, and into the second set of passages.

13. The system of claim 12 , wherein an outlet port of the energy recovery device is directly coupled to an exhaust passage within the heat exchanger.

14. The system of claim 12 , wherein the heat exchanger includes:
a first inlet port coupled to each of the intake system, via a first valve, and the first set of passages;
a second inlet port directly coupled to the energy recovery device and the second set of passages;
a first outlet port coupled to the first set of passages and selectively coupled to each of the intake system, upstream of a compressor via a second valve and the exhaust system via a third valve; and
a second outlet port coupled to the second set of passages and selectively coupled to each of the intake system upstream of the compressor, the intake system downstream of the compressor, and the exhaust system via a fourth valve.

15. The system of claim 14 , wherein the energy recovering device is selectively fluidly coupled to each of the exhaust system upstream of a first exhaust catalyst and a turbine and the exhaust system downstream of the turbine via a fifth valve.

16. The system of claim 15 , further comprising a controller including memory with non-transitory computer-readable instructions for adjusting one or more of the first, second, third, fourth, and fifth valves based on an output of the energy recovery device.

17. The system of claim 12 , wherein the heat exchanger further includes a third set of passages configured to flow coolant, where the third set of passages are positioned between each of the first set of passages and second set of passages.

18. The system of claim 12 , wherein the energy recovery device includes a thermoelectric generator adapted to convert thermal energy from exhaust gases to electrical energy and output the electrical energy to a battery electrically coupled to the energy recovery device.

19. A system, comprising:
a heat exchanger including a first set of passages configured to flow intake air from an intake system and selectively to each of the intake system and an exhaust system, a second set of passages configured to flow exhaust gas from an exhaust system and selectively to each of the intake system upstream of a compressor, the intake system downstream of a compressor, and the exhaust system, and a third set of passages configured to circulate coolant;
an energy recovery device physically and fluidly coupled with the heat exchanger and including a fourth set of passages directly coupled between the exhaust system and the second set of passages; and
a controller including non-transitory memory with computer readable instructions for:
adjusting a flow of one or more of intake air thorough the first set of passages, exhaust gas through the second set of passages, and coolant through the third set of passages based on an amount of energy generated by the energy recovery device.

20. The system of claim 19 , further comprising an electrical component electrically coupled to a battery electrically coupled to and receiving electrical energy from the energy recovery device and wherein the computer readable instructions further include instructions for operating the electrical component using energy stored at the battery via the energy recovery device.

Assignees

• Ford Global Tech Llc

Inventors

• Zhang Xiaogang

Classifications

• F02M26/05

  High pressure loops, i.e. wherein recirculated exhaust gas is taken out from the exhaust system upstream of the turbine and reintroduced into the intake system downstream of the compressor · CPC title

• F02M26/28

  with liquid-cooled heat exchangers · CPC title

• F02M26/02

  EGR systems specially adapted for supercharged engines · CPC title

• F02M35/10268

  Heating, cooling or thermal insulating means (air coolers F02B29/04; thermal treatment of combustion-air, fuel or fuel-air mixture F02M31/00; details of the throttle valve housing F02D9/1035) · CPC title

• F02D41/0077

  Control of the EGR valve or actuator, e.g. duty cycle, closed loop control of position (EGR valve position sensor F02M26/48) · CPC title