Patent ID: 8625098
Filing Date: 2014-01-07
Classification: F02C,F02D,F05D,G01J,G01N

Abstract:
1. A system for a real-time monitoring of an equivalence ratio of a gas-fuel mixture of a gas turbine engine, the system comprising: a plurality of optical probes arranged on a plurality of fuel nozzles for transmitting laser beams directly through a gas-fuel mixture or indirectly by reflecting the laser beams from a surface of a center body or burner tube of the fuel nozzle; wherein the plurality of optical probes comprises a first optical probe and a second optical probe mounted circumferentially or axially on the burner tube such that the laser beams transmitted between the first optical probe and the second optical probe after reflection from the surface of the fuel nozzle follows a pathway that subtends an optimal angle at the surface; one or more detectors for receiving the transmitted laser beams from the plurality of optical probes; and a data acquisition subsystem for acquiring and processing signals from the one or more detectors, using a technique of a fixed wavelength modulation spectroscopy (WMS) with a second-harmonic signal detection, for determining the equivalence ratio of the gas-fuel mixture of the gas turbine engine in real time.