Hybrid combustion in a diesel engine

• US 7,461,627 B2
• Filed: 04/27/2006
• Issued: 12/09/2008
• Est. Priority Date: 04/27/2006
• Status: Active Grant

• Current Assignee: International Engine Intellectual Property Company, LLC (Volkswagen AG)
• Original Assignee: International Engine Intellectual Property Company, LLC (Volkswagen AG)
• Inventors: Liu, Zhengbai, Wei, Puning
• Primary Examiner(s): TRIEU, THAI BA
• Application Number:
  US11/380,537
• Publication Number:
  US 20070251234A1
• Time in Patent Office: 957 Days
• Field of Search: 606/052, 606/01, 123/568.21, 123/568.2, 123294-295, 123/305, 123/481, 701/108
• US Class Current: 123/295
• CPC Class Codes: F02B 1/12 with compression ignition with fuel-air charge ignited by compression ignition of an additional fuel F02B7/00
• CPC Class Codes: F02B 29/0412 Multiple heat exchangers arranged in parallel or in series
• CPC Class Codes: F02B 3/06 with compression ignition compression ignition engines using air or gas for blowing fuel into compressed air in cylinder F02B13/02
• CPC Class Codes: F02B 37/007 with exhaust-driven pumps arranged in parallel , e.g. at least one pump supplying alternatively
• CPC Class Codes: F02B 9/04 Methods of operating
• CPC Class Codes: F02D 23/02 the engines being of fuel-injection type
• CPC Class Codes: F02D 41/0057 Specific combustion modes combustion modes per se F02D41/3017
• CPC Class Codes: F02D 41/0065 Specific aspects of external EGR control constructional details of EGR system F02M26/00
• CPC Class Codes: F02D 41/0082 per groups or banks F02D41/0087 takes precedence
• CPC Class Codes: F02D 41/3035 a mode being the premixed charge compression-ignition mode
• CPC Class Codes: F02M 26/08 for engines having two or more intake charge compressors or exhaust gas turbines, e.g. a turbocharger combined with an additional compressor
• CPC Class Codes: F02M 26/24 with two or more coolers
• CPC Class Codes: F02M 26/38 with two or more EGR valves disposed in parallel
• CPC Class Codes: F02M 26/42 having two or more EGR passages; EGR systems specially adapted for engines having two or more cylinders
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A compression ignition engine (10) has a control system (40), one or more combustion chambers (12), and fuel injectors (42, 44) for injecting fuel into the combustion chambers. The control system controls fueling using a result of the processing of engine speed and engine load to select a particular domain for engine operation (HCCI, HCCI+CD, or CD, —FIG. 1). When the processing selects HCCI, the engine is fueled to cause alternative diesel combustion (such as HCCI) in all combustion chambers. When the processing selects CD, all combustion chambers are fueled for conventional diesel combustion. When the processing selects HCCI+CD, a first group of combustion chambers are fueled for HCCI combustion and a second group for CD combustion. Each group (G1, G2) has its own EGR valve (34, 38) and turbocharger (22, 24).

Claims

1. A method of operating a compression ignition engine having multiple combustion chambers comprising:

processing certain data to select one of plural fueling modes for operating the engine, and

a) when the result of the processing selects a first fueling mode, i) fueling each combustion chamber during an engine cycle to cause alternative diesel combustion, ii) operating a first turbocharger to create charge air in a first intake manifold serving a first group of combustion chambers, iii) recirculating exhaust gas from the first group of combustion chambers through a first EGR valve to the first intake manifold, iv) operating a second turbocharger to create charge air in a second intake manifold serving a second group of combustion chambers, v) recirculating exhaust gas from the second group of combustion chambers through a second EGR valve to the second intake manifold;

b) when the result of the processing selects a second fueling mode, i) fueling each combustion chamber during an engine cycle to cause conventional diesel combustion, ii) operating the first turbocharger to create charge air in the first intake manifold, iii) recirculating exhaust gas from the first group of combustion chambers through the first EGR valve to the first intake manifold, iv) operating the second turbocharger to create charge air in the second intake manifold, v) recirculating exhaust gas from the second group of combustion chambers through the second EGR valve to the second intake manifold, and

c) when the result of the processing selects a third fueling mode, i) fueling each combustion chamber of the first group during an engine cycle to cause alternative diesel combustion, ii) fueling each combustion chamber of the second group during an engine cycle to cause conventional diesel combustion, iii) operating the first turbocharger to create charge air in the first intake manifold, iv) recirculating exhaust gas from the first group of combustion chambers through the first EGR valve to the first intake manifold, v) operating the second turbocharger to create charge air in the second intake manifold, and vi) recirculating exhaust gas from the second group of combustion chambers through the second EGR valve to the second intake manifold.

2. A method as set forth in claim 1 wherein the step of processing certain data to select one of plural fueling modes for operating the engine comprises processing engine speed data and engine load data to select step a) when the processing of engine speed data and engine load data discloses engine operation in a speed/load domain defined by relatively low engine speed and relatively small engine load, to select step b) when the processing of engine speed data and engine load data discloses engine operation in a speed/load domain defined by relatively high engine speed and relatively large engine load, and to select step c) when the processing of engine speed data and engine load data discloses engine operation in a speed/load domain defined by engine speed that is intermediate the relatively low and the relatively high engine speeds and by engine load that is intermediate the relatively small and the relatively large engine loads.

3. A method as set forth in claim 2 wherein in a graph of engine speed vs. engine load whose origin corresponds to zero speed and zero load, the speed/load domain defined by relatively low engine speed and relatively small engine load bounds the origin, the speed/load domain defined by engine speed that is intermediate the relatively low and the relatively high engine speeds and by engine load that is intermediate the relatively small and the relatively large engine loads bounds the speed/load domain defined by relatively low engine speed and relatively small engine load, and the speed/load domain defined by relatively high engine speed and relatively large engine load bounds the speed/load domain defined by engine speed that is intermediate the relatively low and the relatively high engine speeds and by engine load that is intermediate the relatively small and the relatively large engine loads.

4. A compression ignition engine comprising:

a control system for processing data;

multiple combustion chambers;

a fueling system for injecting fuel into the combustion chambers;

a first turbocharger for creating charge air in a first intake manifold serving a first combustion chamber group formed by some of the combustion chambers,

a second turbocharger for creating charge air in a second intake manifold serving a second combustion chamber group formed by the remaining combustion chambers,

a first exhaust gas recirculation system for recirculating exhaust gas from the first combustion chamber group through a first EGR valve to the first intake manifold; and

a second exhaust gas recirculation system for recirculating exhaust gas from the second combustion chamber group through a second EGR valve to the second intake manifold;

wherein the control system controls the fueling system using a result of the processing of certain data by the control system to select one of plural fueling modes for operating the engine such that a) when the result of the processing selects a first fueling mode, each combustion chamber is fueled during an engine cycle to cause alternative diesel combustion, b) when the result of the processing selects a second fueling mode, each combustion chamber is fueled during an engine cycle to cause conventional diesel combustion, and c) when the result of the processing selects a third fueling mode, each combustion chamber of the first group is fueled during an engine cycle to cause alternative diesel combustion and each combustion chamber of the second group is fueled during an engine cycle to cause conventional diesel combustion,

wherein the control system controls both the first and second turbochargers using a result of the processing of certain data by the control system to control turbocharger operation in each fueling mode consistent with the respective mode, and

wherein the control system controls both the first and second EGR valves using a result of the processing of certain data by the control system to control exhaust gas recirculation in each fueling mode consistent with the respective mode.

5. An engine as set forth in claim 4 wherein control system processes engine speed data and engine load data to select the first fueling mode when the processing of engine speed data and engine load data discloses engine operation in a speed/load domain defined by relatively low engine speed and relatively small engine load, to select the second fueling mode when the processing of engine speed data and engine load data discloses engine operation in a speed/load domain defined by relatively high engine speed and relatively large engine load, and to select the third fueling mode when the processing of engine speed data and engine load data discloses engine operation in a speed/load domain defined by engine speed that is intermediate the relatively low and the relatively high engine speeds and by engine load that is intermediate the relatively small and the relatively large engine loads.

6. An engine as set forth in claim 5 wherein in a graph of engine speed vs. engine load whose origin corresponds to zero speed and zero load, the speed/load domain defined by relatively low engine speed and relatively small engine load bounds the origin, the speed/load domain defined by engine speed that is intermediate the relatively low and the relatively high engine speeds and by engine load that is intermediate the relatively small and the relatively large engine loads bounds the speed/load domain defined by relatively low engine speed and relatively small engine load, and the speed/load domain defined by relatively high engine speed and relatively large engine load bounds the speed/load domain defined by engine speed that is intermediate the relatively low and the relatively high engine speeds and by engine load that is intermediate the relatively small and the relatively large engine loads.