Methods and apparatus for rapid sensing of fuel wobbe index

Patent metadata

Field	Value
Publication number	US-9249737-B2
Application number	US-201313777685-A
Country	US
Kind code	B2
Filing date	Feb 26, 2013
Priority date	Feb 26, 2013
Publication date	Feb 2, 2016
Grant date	Feb 2, 2016

Abstract

A sensor apparatus and methods for facilitating combustion of a gaseous fuel are provided. The sensor apparatus comprises a combustion apparatus defining a combustion chamber therein. The combustion apparatus is configured to combust a fuel-air mixture within the combustion chamber to produce at least one combustion product. At least one optical diagnostic apparatus is coupled to the combustion apparatus for measuring at least one property of the at least one combustion product within the combustion chamber. A controller is coupled to the at least one optical diagnostic apparatus, and is configured to determine the Wobbe index of the fuel in real-time based on the measured at least one property of the at least one combustion product and pre-determined combustion state data stored within the controller.

First claim

What is claimed is:

1. A method of facilitating combustion of a gaseous fuel in a gas turbine combustion section of a gas turbine, said method comprising:
extracting a portion of the gaseous fuel prior to the gaseous fuel being supplied to the gas turbine;
supplying the extracted portion of the gaseous fuel to a sensor apparatus comprising a reference combustion chamber;
combusting a fuel-air mixture in the reference combustion chamber to yield at least one combustion product;
measuring at least one property of the at least one combustion product using at least one optical diagnostic sensor apparatus;
determining the Wobbe index of the fuel in real-time based on the measured at least one property of the at least one combustion product;
controlling the combustion in the gas turbine based on the determined Wobbe index.

2. The method of claim 1 , wherein the at least one combustion product is at least one of a flame produced by the reference combustion chamber and exhaust gases generated in the reference combustion chamber, and wherein the at least one property of the at least one combustion product is one of a temperature of the flame and a temperature of the exhaust gases.

3. The method of claim 1 , wherein the at least one optical diagnostic sensor apparatus is a tunable diode laser absorption spectroscopy apparatus that includes a transmitter configured to transmit a laser beam and a receiver configured to receive the laser beam, wherein measuring the at least one property comprises:
transmitting the laser beam, using the transmitter, across the reference combustion chamber through the at least one combustion product; and
receiving the laser beam using the receiver.

4. The method of claim 1 , wherein the at least one optical diagnostic sensor apparatus is an emission spectroscopy apparatus that includes a collection lens, wherein measuring the at least one property comprises collecting ultraviolet emissions from the at least one combustion product using the collection lens.

5. The method of claim 1 , wherein the at least one optical diagnostic sensor apparatus is a fiber pyrometry apparatus that includes a fiber and an infrared sensor, wherein measuring the at least one property comprises detecting infrared emissions, using the infrared sensor, from the fiber positioned within the combustion chamber.

6. The method of claim 1 , wherein the at least one diagnostic sensor apparatus is an oxygen sensing apparatus that includes an oxygen sensor, wherein measuring the at least one property comprises measuring the oxygen content of the at least one combustion product using the oxygen sensor.

7. The method of claim 1 further comprising channeling the fuel through a first flow restriction device and channeling air through a second flow restriction device, wherein the first flow restriction device measures at least one of the specific gravity of the fuel, the mass flow of the fuel, and the differential pressure of the fuel across the first flow restriction device, and wherein the second flow restriction device measures the differential pressure of the air across the second flow restriction device.

8. The method of claim 7 further comprising:
storing pre-determined combustion state data associated with the combustion of the fuel in a controller;
utilizing the measured at least one property of the at least one combustion product, the pre-determined combustion state data stored in the controller, and at least one of the measured specific gravity of the fuel, mass flow of the fuel, and differential pressures of the fuel and air across the first and second flow restriction devices to determine the Wobbe index of the fuel.

9. A sensor apparatus comprising:
a reference combustion chamber, wherein said sensor apparatus is configured to receive fuel from a fuel supply line, to receive air from an air supply line, and to combust a fuel-air mixture within said reference combustion chamber to produce at least one combustion product;
at least one optical diagnostic apparatus coupled to said reference combustion chamber, said at least one optical diagnostic apparatus configured to measure a temperature of the at least one combustion product within said reference combustion chamber;
a first flow restriction device positioned in the fuel supply line and configured to measure at least one of a specific gravity of said fuel, a mass flow of said fuel, and a differential pressure of said fuel across said first flow restriction device;
a second flow restriction device positioned in the air supply line and configured to measure a differential pressure of air across said second flow restriction device; and
a controller coupled to said at least one optical diagnostic apparatus and said first and second flow restriction devices, said controller configured to determine the Wobbe index of the fuel in real-time based on said measured temperature, said measured at least one of a specific gravity of said fuel, a mass flow of said fuel, and a differential pressure of said fuel across said first flow restriction device, and said differential pressure of air across said second flow restriction device.

10. The sensor apparatus of claim 9 , wherein said at least one optical diagnostic apparatus comprises is a tunable diode laser absorption spectroscopy apparatus comprising a transmitter configured to transmit a laser beam across said reference combustion chamber through the at least one combustion product, said tunable diode laser absorption spectroscopy apparatus further comprising a receiver configured to receive the laser beam.

11. The sensor apparatus of claim 9 , wherein said at least one optical diagnostic apparatus is an emission spectroscopy apparatus comprising a collection lens, wherein said emission spectroscopy apparatus is configured to collect ultraviolet emissions from the at least one combustion product using said collection lens.

12. The sensor apparatus of claim 9 , wherein said at least one optical diagnostic apparatus is a fiber pyrometry apparatus comprising an infrared sensor, wherein said fiber pyrometry apparatus is configured to detect infrared emissions from a fiber positioned within said reference combustion chamber using said infrared sensor.

13. A gas turbine engine system comprising;
a fuel source configured to supply a gas turbine combustion section of the gas turbine engine system with a fuel through a primary fuel supply line;
a sensor apparatus coupled in fluid communication with said fuel source through a secondary fuel supply line configured for extracting a portion of the fuel from the primary fuel supply line prior to the fuel being supplied to the gas turbine, said sensor apparatus comprising:
a combustion apparatus defining a reference combustion chamber therein, wherein said combustion apparatus is configured to combust a fuel-air mixture within said reference combustion chamber to produce at least one combustion product; and
at least one optical diagnostic apparatus coupled to said combustion apparatus, said at least one diagnostic apparatus configured to measure at least one property of the at least one combustion product within said reference combustion chamber; and

a controller coupled to said sensor apparatus and configured to determine the Wobbe index of said fuel in real-time based on said measured at least one property of the at least one combustion product and pre-determined combustion state data stored within said controller and to provide signals for controlling combustion in the gas turbine combustion section based on the determined Wobbe index.

14. The gas turbine engine system of claim 13 , wherein the at least

Assignees

• Gen Electric

Inventors

• Fitzgerald Russell Paul
• Pastecki Patrick Edward
• Kalitan Danielle Marie
• Leonard Gary Lee

Classifications

• F05D2270/083

  by monitoring combustion conditions · CPC title

• F05D2260/80

  Diagnostics · CPC title

• F02C9/26 Primary

  Control of fuel supply (F02C9/48 takes precedence; fuel valves F02C7/232) · CPC title

• Y02T50/677

  Cross-Sectional Technologies · mapped topic

• F05D2270/804

  Optical devices · CPC title