Interstage gas injection for multi-stage turbocharged natural gas engine

Patent metadata

Field	Value
Publication number	US-9574490-B2
Application number	US-201313948239-A
Country	US
Kind code	B2
Filing date	Jul 23, 2013
Priority date	Jul 23, 2013
Publication date	Feb 21, 2017
Grant date	Feb 21, 2017

Abstract

A turbocharged internal combustion engine system includes at least one high pressure turbocharger and at least one low pressure turbocharger arranged in series. A fuel source that provides fuel for gaseous fuel induction operation of the engine is connected to inject fuel between the low pressure compressor of the low pressure turbocharger and the high pressure compressor of the high pressure turbocharger.

First claim

What is claimed is:

1. An internal combustion engine system, comprising:
an internal combustion engine including at least one intake system for delivering a charge flow to at least a portion of a plurality of cylinders of the internal combustion engine and at least one exhaust system for receiving exhaust gas from at least a portion of the plurality of cylinders;
at least one high-pressure turbocharger with a first high pressure turbine in the exhaust system and at least one low pressure turbocharger with a first low pressure turbine in the exhaust system downstream of the first high pressure turbine;
the low pressure turbocharger further including a first low pressure compressor operably connected to the low pressure turbine with the low pressure compressor in the intake system to receive and compress intake air, and the high pressure turbocharger further including a first high pressure compressor operably connected with the first high pressure turbine with the first high pressure compressor in the intake system downstream of the low pressure compressor;
an intercooler in the intake system passage between the low pressure compressor and the high pressure compressor for cooling the intake air compressed by the low pressure compressor; and
a fuel injector connected to the intake system between the low pressure compressor and the high pressure compressor downstream of the intercooler, the fuel injector being operably connected to a pressurized fuel source to provide a pressurized gaseous fuel to the compressed intake air between the low pressure compressor and the high pressure compressor and form the charge flow for compression by the high pressure compressor, wherein the pressurized gaseous fuel is 30-40 pounds per square inch.

2. The system of claim 1 , further comprising a wastegate connected to the exhaust system around the high pressure turbine.

3. The system of claim 1 , further comprising an aftercooler in the intake system downstream of the high pressure compressor and upstream of an intake manifold of the internal combustion engine for cooling the charge flow compressed by the high pressure compressor.

4. The system of claim 1 , further comprising a throttle in the intake system between the high pressure compressor and an intake manifold of the internal combustion engine to regulate the charge flow to the plurality of cylinders.

5. The system of claim 1 , wherein the at least one high pressure turbocharger includes at least two high pressure turbochargers with respective first and second high pressure turbines connected to respective ones of first and second exhaust passages of the exhaust system.

6. The system of claim 5 , wherein the at least two high pressure turbochargers further include respective first and second high pressure compressors that are connected to respective ones of first and second intake passage portions of the intake system, wherein the first and second intake passage portions connect to one another at a common intake passage portion downstream of the first and second high speed compressors.

7. The system of claim 6 , further comprising an aftercooler in the common intake passage portion for cooling the charge flow from the first and second high pressure compressors.

8. The system of claim 6 , wherein the common intake passage portion is connected to first and second intake manifold portions that are connected to respective first and second portions of the plurality of cylinders.

9. The system of claim 6 , wherein the at least one low pressure turbocharger includes at least two low pressure turbochargers with respective first and second low pressure turbines connected to respective ones of the first and second exhaust passages.

10. The system of claim 9 , wherein the at least two low pressure turbochargers further include respective first and second low pressure compressors connected to respective ones of third and fourth intake passage portions, wherein compressed intake air from the first and second low pressure compressors combine in a second common intake passage portion and the fuel injector is connected to the second common intake passage portion to provide fuel to the compressed intake air.

11. The system of claim 10 , further comprising an intercooler in the second common intake passage portion for cooling the intake air compressed by the first and second low pressure compressors.

12. The system of claim 1 , further comprising a multi-stage bypass in the intake system configured to selectively bypass at least a portion of the charge flow from downstream of the high pressure compressor to upstream of the low pressure compressor.

13. The system of claim 12 , further comprising a single stage bypass in the intake system configured to selectively bypass at least a portion of the charge flow from downstream of the high pressure compressor to an interstage location between the low pressure compressor and the high pressure compressor.

14. The system of claim 12 , further comprising a single stage bypass in the intake system configured to selectively bypass at least a portion of the intake air from an interstage location between the low pressure compressor and the high pressure compressor to upstream of the low pressure compressor.

15. The system of claim 1 , wherein the pressurized gaseous fuel is one of natural gas, methane, or propane.

16. An internal combustion engine system, comprising:
an internal combustion engine including at least one intake system for delivering a charge flow to at least a portion of a plurality of cylinders of the internal combustion engine and at least one exhaust system for receiving exhaust gas from at least a portion of the plurality of cylinders;
at least one high-pressure turbocharger with a first high pressure turbine in the exhaust system and at least one low pressure turbocharger with a first low pressure turbine in the exhaust system downstream of the first high pressure turbine;
the low pressure turbocharger further including a first low pressure compressor operably connected to the low pressure turbine with the low pressure compressor connected in the intake system to receive and compress intake air, and the high pressure turbocharger further including a first high pressure compressor operably connected with the first high pressure turbine with the first high pressure compressor connected in the intake system downstream of the low pressure compressor;
a fuel injector connected to the intake system between the low pressure compressor and the high pressure compressor, wherein the fuel injector is operably connected to a pressurized fuel source to provide a pressurized gaseous fuel to the intake air between the low pressure compressor and the high pressure compressor and form the charge flow for compression by the high pressure compressor, wherein the pressurized gaseous fuel is 30-40 pounds per square inch; and
a multi-stage bypass configured to selectively bypass at least a portion of the charge flow in the intake system from a first location that is downstream of the high pressure compressor to a second location that is upstream of the low pressure compressor.

17. The system of claim 16 , further comprising a single stage bypass configured to selectively bypass charge flow in the intake system from the first location to an interstage location that is between the low pressure compressor and the high pressure compressor.

18. The system of claim 16 , further comprising a single stage bypass that is configured to selectively bypass inlet air in the intake system from an interstage location that is b

Assignees

• Cummins Inc

Inventors

• Watanabe Atsuhiko

Classifications

• F02M21/0206

  Non-hydrocarbon fuels, e.g. hydrogen, ammonia or carbon monoxide · CPC title

• Y02T10/32

  Cross-Sectional Technologies · mapped topic

• F02B29/0412

  Multiple heat exchangers arranged in parallel or in series · CPC title

• Y02T10/144

  Cross-Sectional Technologies · mapped topic

• Y02T10/146

  Cross-Sectional Technologies · mapped topic