Engine systems and methods for operating an engine

• US 9,752,537 B2
• Filed: 05/20/2015
• Issued: 09/05/2017
• Est. Priority Date: 05/30/2014
• Status: Active Grant

• Current Assignee: Cummins Incorporated
• Original Assignee: Cummins Incorporated
• Inventors: Dale, Adrian P., Dolton, Michael D., Geckler, Samuel C., McEwen, James Alexander, Sharp, Nicholas Kenneth, Garrett, Stephen Edward, Perfetto, Anthony Kyle
• Primary Examiner(s): Bogue, Jesse
• Application Number:
  US14/717,566
• Publication Number:
  US 20150345433A1
• Time in Patent Office: 839 Days
• CPC Class Codes: F01D 9/026 Scrolls for radial machines or engines
• CPC Class Codes: F01N 13/107 More than one exhaust manifold or exhaust collector
• CPC Class Codes: F02B 37/025 Multiple scrolls or multiple gas passages guiding the gas to the pump drive
• CPC Class Codes: F02C 6/12 Turbochargers, i.e. plants for augmenting mechanical power output of internal-combustion piston engines by increase of charge pressure
• CPC Class Codes: F02M 26/43 in which exhaust from only one cylinder or only a group of cylinders is directed to the intake of the engine
• CPC Class Codes: F05D 2220/40 in turbochargers
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

A unique engine system has an engine with a dedicated exhaust gas recirculation cylinder, an EGR system that receives exhaust gas from the dedicated cylinder, and a turbocharger having turbine inlet ports in fluid communication with other engine cylinders via a plurality of exhaust passages. At least two of the exhaust passages are substantially isolated from each other. Other embodiments include apparatuses, systems, devices, hardware, methods, and combinations for engines and engine systems.

Claims

1. An engine system, comprising:

an internal combustion piston engine having a plurality of combustion cylinders, at least a first cylinder of which is a dedicated exhaust gas recirculation (EGR) cylinder;

an EGR system operative to receive exhaust gas from the engine and direct at least a portion of the exhaust gas to the plurality of combustion cylinders for intake during engine operation;

a turbocharger having a turbine with a plurality of inlet ports to the turbine, wherein the inlet ports are adjacent to the turbine and are spaced apart from each along the turbine;

a plurality of exhaust passages, including;

a first exhaust passage fluidly coupling the dedicated EGR cylinder with the EGR system and operative to supply exhaust gases from the dedicated EGR cylinder to the EGR system;

a second exhaust passage fluidly coupling, a second cylinder of the plurality of combustion cylinders to a first, inlet port of the plurality of inlet ports of the turbine;

a third exhaust passage fluidly coupling a third cylinder of the plurality of combustion cylinders to a second inlet port of the plurality of inlet ports of the turbine, wherein the third exhaust passage is fluidly isolated from the second exhaust passage, the first exhaust passage is fluidly isolated from the turbine, and the first exhaust passage is fluidly isolated from the second and third exhaust passages; and

a fourth exhaust passage fluidly coupling a fourth cylinder of the plurality of combustion cylinders to a third inlet port of the plurality of inlet ports of the turbine, wherein the fourth exhaust passage is fluidly isolated from the first, second, and third exhaust passages.

2. The engine system of claim 1, wherein the second and third exhaust passages are structured to separate pressure events originating in the second cylinder from pressure events originating in the third cylinder.

3. The engine system of claim 1, further comprising at least one passage including a valve, and with the valve open, the at least one passage is configured and operative to direct exhaust gases from the first exhaust passage to the turbocharger.

4. The engine system of claim 1, wherein the inlet ports are spaced apart from each other along the turbine in an axial direction.

5. The engine system of claim 1, wherein the inlet ports are spaced apart from each other along the turbine in a circumferential direction.

6. The engine system of claim 1, further comprising a wastegate valve operative to bleed exhaust gases from at least one of the second exhaust passage and the third exhaust passage.

7. An engine system, comprising:

an EGR system;

a turbocharger having a turbine; and

an internal combustion piston engine having a first cylinder in fluid communication with the EGR system through a first exhaust passage;

a second cylinder in direct fluid communication with the turbine through a second exhaust passage; and

a third cylinder in fluid communication with the turbine through a third exhaust passage, wherein the first exhaust passage, the second exhaust passage, and the third exhaust passage are in fluid isolation from each other and the first exhaust passage is in fluid isolation from the turbine, and further comprising a fourth cylinder and a fourth exhaust passage and the fourth cylinder is in fluid communication with the turbine through the fourth exhaust passage, wherein the first, second, third and fourth exhaust passages are in fluid isolation from each other and each of the second, third and fourth exhaust passages is connected to the turbine with respective ones of first, second and third inlet ports to the turbine, and each of the first, second and third inlet ports includes a wastegate.

8. A method of operating an engine, comprising:

delivering exhaust gases from a first cylinder of an internal combustion engine as dedicated EGR cylinder to an EGR system through a first exhaust passage;

delivering exhaust gases from a second cylinder of the internal combustion engine to a first inlet port of a turbine of a turbocharger through a second exhaust passage;

delivering exhaust gases from a third cylinder of the internal combustion engine to a second inlet port of the turbine through a third exhaust passage;

delivering exhaust gases from a fourth cylinder of the internal combustion engine to a third inlet port of the turbine through a fourth exhaust passage; and

fluidly isolating the exhaust gases in the second exhaust passage from the exhaust gases in the third exhaust passage prior to entry into the turbine, fluidly isolating the exhaust gases in the first exhaust passage from the turbine, and fluidly isolating the exhaust gases in the first exhaust passage from the exhaust gases in the second and third exhaust passages, wherein the exhaust gases in the fourth exhaust passage are fluidly isolated from the exhaust gases in the first, second and third exhaust passages.