US 6,071,114 AGranted

Method and apparatus for characterizing a combustion flame

AssigneeMeggitt Avionics, Inc.

InventorsDeidre E. Cusack, Leo Jubinville, Jonathan Plimpton

Life of this patent

Estimating the term…

Loading patent…

Abstract

Characteristics of a flame within a turbine or burner are determined based upon ultraviolet, visible, and infrared measurements of the flame. The measurements include the amplitude of frequency bands that are indicative of an efficient combustion process, such as those that increase when the flame temperature increases. The measurements also include the amplitude of frequency bands that are indicative of an inefficient combustion process, such as those that do not vary, increase a relatively small amount, or decrease when the flame temperature increases. The temperature of the flame may therefore be determined accurately, to facilitate efficient operation of the turbine or burner, while minimizing polluting emissions.

Claims24

Dependent claims

A system for characterizing a combustion flame in a combustion chamber, comprising:

a first sensor having an input that receives energy within a first frequency band of the flame, and an output that provides a first signal indicative of an amplitude of the energy within the first frequency band;
a second sensor having an input that receives energy within a second frequency band of the flame, different from the first frequency band, and an output that provides a second signal indicative of an amplitude of the energy within the second frequency band;
and
a flame characterization module having a first input coupled to the output of the first sensor, a second input coupled to the output of the second sensor, and an output that provides a figure of merit that characterizes the combustion flame as a function of at least a ratio of the first signal to the second signal;
wherein the first frequency band is chosen to be a predetermined band characteristic of an efficient combustion process wherein an efficient combustion process is characterized by at least one of a minimized waste stream pollutant emission level and a maximized power output level per unit measure of fuel;
and
wherein the second frequency band is chosen to be a predetermined band characteristic of an inefficient combustion process wherein an inefficient combustion process is characterized by at least one of a high level of NO.sub.x, a high level of SO.sub.x, a high level of CO.sub.2, a high level of unburned hydrocarbons, a high level of particulate matter, and a lower power output level per unit measure of fuel.

4 more elements

A method of characterizing a combustion flame in a combustion chamber, comprising:

(a) measuring an amplitude of energy within a first frequency band of the flame, the first frequency band indicative of an efficient combustion process wherein an efficient combustion process is characterized by at least one of a minimized waste stream pollutant emission level and a maximized power output level per unit measure of fuel;
(b) measuring an amplitude of energy within a second frequency band of the flame, the second frequency band indicative of an inefficient combustion process and different from the first frequency band, wherein an inefficient combustion process is characterized by at least one of a high level of NO.sub.x, a high level of SO.sub.x, a high level of CO.sub.2, a high level of unburned hydrocarbons, a high level of particulate matter, and a lower power output level per unit measure of fuel;
and
(c) determining a figure of merit to characterize the combustion flame as a function of at least a ratio of the amplitude of energy within the first frequency band to the amplitude of energy within the second frequency band.

1 more element

An apparatus for characterizing a combustion flame in a combustion chamber, comprising:

first means for measuring an amplitude of energy within a first frequency band of the flame, the first frequency band indicative of an efficient combustion process wherein
an efficient combustion process is characterized by at least one of a minimized waste stream pollutant emission level and a maximized power output level per unit measure of fuel;
second means for measuring an amplitude of energy within a second frequency band of the flame, the second frequency band indicative of an inefficient combustion process and different from the first frequency band, wherein an inefficient combustion process is characterized by at least one of a high level of NO.sub.x, a high level of SO.sub.x, a high level of CO.sub.2, a high level of unburned hydrocarbons, a high level of particulate matter, and a lower power output level per unit measure of fuel;
and
third means for determining a figure of merit to characterize the combustion flame as a function of at least a ratio of the amplitude of energy within the first frequency band to the amplitude of energy within the second frequency band.

2 more elements

Dependencies are inferred from the claim text.

Facts

Application: 08/985,836Filed 5 Dec 1997 · continuation
Priority: 19 Jun 1996
Granted: 6 Jun 2000
Term ends: Not estimatedThe source records don’t support an estimate.

Classification14 codes

F23N 5/082
Using light-sensitive elements: using electronic means
F01D 17/02
Regulating or controlling by varying flow: arrangement of sensing elements
F01D 21/003
Shutting-down of machines or engines, e.g. in emergency; Regulating, controlling, or safety means not otherwise provided for: arrangements for…
F02C 9/00
Controlling gas-turbine plants