Abstract: A fuel-air mixer for use with a combustor is provided. The fuel-air mixer includes an outer ring, an intermediate hub disposed coaxially within the outer ring such that a first plenum is formed therebetween, and an inner hub disposed coaxially within the intermediate hub such that a second plenum is formed therebetween. A first swirler including a plurality of first swirler vanes is positioned between the outer ring and the intermediate hub, wherein the first swirler is configured to rotate fluid flowing therethrough in a first direction. A second swirler including a plurality of second swirler vanes is positioned between the intermediate hub and the inner hub, wherein the second swirler is configured to rotate fluid flowing therethrough in a second direction. A plurality of fuel injection conduits are also defined within the fuel-air mixer for channeling fuel to the first and second plenums.

Abstract: A fuel-air mixer for use with a combustor is provided. The fuel-air mixer includes an outer ring, an intermediate hub disposed coaxially within the outer ring such that a first plenum is formed therebetween, and an inner hub disposed coaxially within the intermediate hub such that a second plenum is formed therebetween. A first swirler including a plurality of first swirler vanes is positioned between the outer ring and the intermediate hub, wherein the first swirler is configured to rotate fluid flowing therethrough in a first direction. A second swirler including a plurality of second swirler vanes is positioned between the intermediate hub and the inner hub, wherein the second swirler is configured to rotate fluid flowing therethrough in a second direction. A plurality of fuel injection conduits are also defined within the fuel-air mixer for channeling fuel to the first and second plenums.

Abstract: A method of monitoring a physical parameter comprises receiving a sensor signal representative of an actual value from each of a plurality of sensors. The method further comprises calculating confidence value for each sensed value and a weighted average of actual values of the sensor signal by weighting each sensed value by the respective confidence value. The weighted average is used to determine a corresponding value of the sensed parameter.

Abstract: Methods and apparatus for operating a gas turbine engine without sustained detrimental levels of dynamic pressure are provided. The engine includes a combustor. The method includes determining the combustor acoustic level amplitude, comparing the acoustic level to a predetermined upper acoustic limit, and adjusting a fuel flow distribution to the combustor using a closed loop controller to facilitate reducing the acoustic level to a predetermined lower acoustic limit that is less than the upper acoustic limit.