Method and apparatus for characterizing a combustion flame

A method of detecting an amount of a contaminant in an enclosure, the method comprising:

• detecting a first amplitude of energy within a first wavelength band of a first width centered about an emission wavelength of the contaminant;
• detecting a second amplitude of energy within a second wavelength band of a second width, larger than the first width, the second wavelength band also centered about the emission wavelength of the contaminant;
• determining a ratio of the first amplitude of energy to the second amplitude of energy;
• and
• comparing the ratio to a known threshold to determine the amount of contaminant in the enclosure.

A system for characterizing a combustion flame, comprising:

• a first sensor having an input that receives energy within a first wavelength band of the flame, and an output that provides a first signal indicative of an amplitude of the energy within the first wavelength band;
• a second sensor having an input that receives energy within a second wavelength band of the flame, different from the first wavelength band, and an output that provides a second signal indicative of an amplitude of the energy within the second wavelength 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 wavelength band includes a wavelength of 2200 nm, representative of an inefficient combustion process;
• and
• wherein the second wavelength band is representative of an efficient combustion process.

A method of characterizing a combustion flame, comprising:

• (a) measuring an amplitude of energy within a first wavelength band of the flame, the first wavelength band indicative of an inefficient combustion process, and outputting a first signal representative of the measured amplitude of energy;
• (b) measuring an amplitude of energy within a second wavelength band of the flame, the second wavelength band indicative of an efficient combustion process and different from the first wavelength band, and outputting a second signal indicative of the measured amplitude of energy;
• and
• (c) determining a figure of merit to characterize the combustion flame as a function of at least a ratio of the first and second signals;
• wherein the first wavelength band includes a wavelength of 2200 nm.

An apparatus for characterizing a combustion flame, comprising:

• first means for measuring an amplitude of energy within a first wavelength band of the flame, the first wavelength band indicative of an inefficient combustion process, and for outputting a first signal indicative of the measured amplitude of energy;
• second means for measuring an amplitude of energy within a second wavelength band of the flame, the second wavelength band indicative of an efficient combustion process and different from the first wavelength band, and for outputting a second signal indicative of the measured amplitude of energy;
• and
• determining means for determining a figure of merit to characterize the combustion flame as a function of at least a ratio of the first and second signals,
• wherein the first wavelength band includes a wavelength of 2200 nm.