Methods and systems for controlling air flow paths in an engine

• US 9,957,876 B2
• Filed: 05/23/2016
• Issued: 05/01/2018
• Est. Priority Date: 05/23/2016
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Zhang, Xiaogang
• Primary Examiner(s): Kwon, John
• Application Number:
  US15/162,409
• Publication Number:
  US 20170335748A1
• Time in Patent Office: 708 Days
• Field of Search: 123 4101, 123 4102, 12356814, 12356815, 12356817, 12356818, 1235682, 60599
• CPC Class Codes: F01N 2240/02 a heat exchanger
• CPC Class Codes: F01N 2900/1804 Properties of secondary air added directly to the exhaust
• CPC Class Codes: F01N 3/2006 Periodically heating or cooling catalytic reactors, e.g. at cold starting or overheating by electrically controlling the supply of combustible mixture or its constituents only F02D41/0235
• CPC Class Codes: F01N 3/30 Arrangements for supply of additional air control, e.g. using by-passes or variable air pump drives, F01N3/22
• CPC Class Codes: F01N 3/306 Preheating additional air
• CPC Class Codes: F01N 9/00 Electrical control of exhaust gas treating apparatus monitoring or diagnostic devices for exhaust-gas treatment apparatus F01N11/00; conjoint electrical control of two or more combustion engine functions F02D43/00
• CPC Class Codes: F01P 3/20 Cooling circuits not specific to a single part of engine or machine F01P3/22 takes precedence
• CPC Class Codes: F01P 7/16 by thermostatic control
• CPC Class Codes: F02B 21/00 Engines characterised by air-storage chambers
• CPC Class Codes: F02B 33/44 Passages conducting the charge from the pump to the engine inlet, e.g. reservoirs
• CPC Class Codes: F02B 37/04 Engines with exhaust drive and other drive of pumps, e.g. with exhaust-driven pump and mechanically-driven second pump
• CPC Class Codes: F02B 37/183 Arrangements of bypass valves or actuators therefor
• CPC Class Codes: F02D 41/0007 for control of turbo-charged or super-charged engines control of the pumps per se F02B37/12
• CPC Class Codes: F02D 41/0065 Specific aspects of external EGR control constructional details of EGR system F02M26/00
• CPC Class Codes: F02D 41/0077 Control of the EGR valve or actuator, e.g. duty cycle, closed loop control of position EGR valve position sensor F02M26/48
• CPC Class Codes: F02D 41/26 using computer, e.g. microprocessor
• CPC Class Codes: F02G 5/00 Profiting from waste heat of combustion engines, not otherwise provided for
• CPC Class Codes: F02M 26/05 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 Class Codes: F02M 26/06 Low pressure loops, i.e. wherein recirculated exhaust gas is taken out from the exhaust downstream of the turbocharger turbine and reintroduced into the intake system upstream of the compressor
• CPC Class Codes: F02M 26/22 with coolers in the recirculation passage
• CPC Class Codes: F02M 26/27 : with air-cooled heat exchangers
• CPC Class Codes: F02M 26/28 : with liquid-cooled heat exchangers
• CPC Class Codes: F02M 26/31 : Air-cooled heat exchangers
• CPC Class Codes: F02M 26/32 : Liquid-cooled heat exchangers
• CPC Class Codes: F02M 26/33 : controlling the temperature of the recirculated gases
• CPC Class Codes: F02M 26/36 : with means for adding fluids other than exhaust gas to the recirculation passage; with reformers
• CPC Class Codes: F02M 26/37 : with temporary storage of recirculated exhaust gas internal exhaust gas recirculation F02M26/01
• CPC Class Codes: F28D 1/0213 : for heating or cooling a liquid in a tank
• CPC Class Codes: F28D 21/0003 : the heat being recuperated from exhaust gases F28D21/0014 takes precedence
• CPC Class Codes: F28D 7/16 : the conduits being arranged in parallel spaced relation F28D7/0008 - F28D7/0058 take precedence; F28D7/02 - F28D7/10 take precedence
• CPC Class Codes: F28F 27/02 : for controlling the distribution of heat-exchange media between different channels static flow control means in header boxes F28F9/026; arrangements of guide plates or guide vanes F28F9/22, F28F25/12
• CPC Class Codes: Y02T 10/12 : Improving ICE efficiencies
• CPC Class Codes: Y02T 10/40 : Engine management systems

Abstract

Methods and systems are provided for controlling the temperature and ratio of gases within a gas mixing tank reservoir and selectively charging/discharging gases from the reservoir to one or both of an intake system or an exhaust system. In one example, a method (or system) may include storing exhaust gas and/or compressed intake air into a gas mixing reservoir, and increasing or decreasing flow of coolant to the reservoir based on engine operating conditions. The stored gases may be discharged to an intake system and/or an exhaust system based on requests from a controller, and coolant flow to the reservoir may be adjusted based on the composition of the gases stored within the reservoir.

Claims

1. A method, comprising:

adjusting a flow of coolant through a gas mixing tank reservoir fluidly coupled to each of an intake system and an exhaust system of an engine in response to a request to supply one or more of secondary air injection to the exhaust system and exhaust gas recirculation to the intake system via the reservoir, based on a temperature of the coolant entering the reservoir, including maintaining flow of coolant through the reservoir in response to the request being a request to supply secondary air injection to the exhaust system in order to increase turbine speed only, regardless of the temperature of the coolant entering the reservoir.

2. The method of claim 1, further comprising, after adjusting the flow of coolant through the reservoir, supplying the one or more of secondary air injection and exhaust gas recirculation as requested in response to a temperature of gases within the reservoir being at a desired temperature, where the desired temperature is based on an indicated location for injecting the gases from the reservoir to one or more of the intake system and the exhaust system.

3. The method of claim 2, further comprising, when the request is a request to supply secondary air injection to the exhaust system, selectively supplying secondary air injection to an exhaust manifold and a turbine bypass disposed around a turbine based on a first temperature of a pre-turbine catalyst and a second temperature of a post-turbine catalyst.

4. The method of claim 3, wherein selectively supplying secondary sir injection includes supplying secondary air injection to the exhaust manifold in response to the first temperature being below a first catalyst light off temperature of the pre-turbine catalyst and supplying secondary air injection to the turbine bypass in response to the second temperature being below a second catalyst light off temperature of the post-turbine catalyst.

5. The method of claim 1, wherein, in response to the request being a request to supply secondary air injection to the exhaust system, adjusting the flow of coolant includes:

increasing the flow of coolant through the reservoir when the coolant temperature is greater than a threshold temperature; and

decreasing the flow of coolant through the reservoir when the coolant temperature is less than the threshold temperature.

6. The method of claim 5, further comprising, after adjusting the flow of coolant through the reservoir, delaying supplying the secondary air injection to the exhaust system until the coolant temperature reaches a desired coolant temperature for secondary air injection.

7. The method of claim 6, wherein the threshold temperature is adjusted based on a gas temperature within the reservoir before the adjusting and the desired coolant temperature for secondary air injection.

8. The method of claim 1, wherein, in response to the request being a request to supply low pressure exhaust gas recirculation to the intake system, upstream of a compressor, adjusting the flow of coolant includes:

increasing the flow of coolant through the reservoir when the coolant temperature is greater than a threshold temperature and condensate is indicated at the compressor or when the coolant temperature is less than the threshold temperature and condensate is not indicated at the compressor; and

decreasing the flow of coolant through the reservoir when the coolant temperature is greater than the threshold temperature and condensate is not indicated at the compressor or when the coolant temperature is less than the threshold temperature and condensate is indicated at the compressor.

9. The method of claim 1, wherein, in response to the request being a request to supply high pressure exhaust gas recirculation to the intake system, downstream of a compressor, adjusting the flow of coolant includes:

increasing the flow of coolant through the reservoir when the coolant temperature is less than a threshold temperature; and

decreasing the flow of coolant through the reservoir when the coolant temperature is greater than the threshold temperature.

10. The method of claim 1, further comprising adjusting the flow of coolant through the reservoir in response to a request to supply air injection to the intake system, upstream of a compressor, based on compressor surge, wherein adjusting the flow of coolant includes:

increasing the flow of coolant through the reservoir when the coolant temperature is greater than a threshold temperature; and

decreasing the flow of coolant through the reservoir when the coolant temperature is less than the threshold temperature.

11. The method of claim 1, further comprising storing gases from one or more of the intake system and the exhaust system in response to one or more of an amount of charge stored within the reservoir being below a threshold level, boost pressure greater than a desired boost pressure for torque demand, and a deceleration fuel shut off condition.

12. A method comprising:

during a first condition, circulating coolant to a gas mixing tank reservoir arranged between an intake system and an exhaust system of an engine and providing one or more of secondary air injection to the exhaust system and exhaust gas recirculation to the intake system via the gas mixing tank reservoir; and

during a second condition, not circulating coolant to the gas mixing tank reservoir and providing one or more of secondary air injection to the exhaust system and exhaust gas recirculation to the intake system via the gas mixing tank reservoir, wherein the first condition includes in response to one or more of;

a request to provide secondary air injection to the exhaust system when a temperature of coolant entering the gas mixing tank reservoir is greater than a first threshold temperature;

a request to provide low pressure exhaust gas recirculation to the intake system, upstream of a compressor, when the temperature of the coolant is greater than a second threshold temperature and condensate is indicated at the compressor;

a request to provide low pressure exhaust gas recirculation to the intake system, upstream of the compressor, when the temperature of the coolant is at or less than the second threshold temperature and condensate is not indicated at the compressor; and

a request to provide high pressure exhaust gas recirculation to the intake system, downstream of the compressor, when the temperature of the coolant is at or less than a third threshold temperature.

13. The method of claim 12, wherein the second condition includes in response to one or more of:

a request to provide secondary air injection to the exhaust system when a temperature of coolant entering the gas mixing tank reservoir is at or less than a first threshold temperature;

a request to provide low pressure exhaust gas recirculation to the intake system, upstream of a compressor, when the temperature of the coolant is greater than a second threshold temperature and condensate is not indicated at the compressor;

a request to provide low pressure exhaust gas recirculation to the intake system, upstream of the compressor, when the temperature of the coolant is at or less than the second threshold temperature and condensate is indicated at the compressor; and

a request to provide high pressure exhaust gas recirculation to the intake system, downstream of the compressor, when the temperature of the coolant is greater than a third threshold temperature.

14. The method of claim 12, further comprising, during the first condition and the second condition, delaying providing one or more of the secondary air injection and the exhaust gas recirculation via the gas mixing tank reservoir until a gas temperature within the gas mixing tank reservoir reaches a desired temperature, where the desired temperature is based on a requested location in the intake system or the exhaust system for injecting gases from the gas mixing temperature reservoir.

15. A system for an engine, comprising:

a gas mixing tank reservoir positioned between an intake system and an exhaust system of the engine including;

a first gas inlet port fluidly coupled to an exhaust manifold;

a second gas inlet port fluidly coupled to an intake passage downstream of a compressor;

a first gas outlet port fluidly coupled to the intake passage;

a second gas outlet port fluidly coupled to the exhaust system;

coolant passages configured to flow coolant through the reservoir; and

a first valve fluidly coupled to the coolant passages and configured to adjust a flow of coolant through the coolant passages, wherein the second gas outlet port is selectively coupled via a second valve to each of the exhaust manifold and a turbine bypass passage disposed around a turbine of the exhaust system.

16. The system of claim 15, further comprising a controller including computer readable instructions for adjusting a position of the first valve in response to a request to supply one or more of gas stored within the reservoir to the exhaust system via the second gas outlet port and gas stored within the reservoir to the intake system via the first gas outlet port, based on a temperature of the coolant entering the coolant passages.

17. The system of claim 15, wherein the first gas outlet port is fluidly coupled to the intake passage upstream of the compressor and wherein the reservoir further comprises a third gas outlet port fluidly coupled to the intake passage downstream of the compressor.