Abstract: A gas turbine engine comprising a set of circumferentially adjacent airfoils, the airfoils having an outer wall defining a pressure side and a suction side extending between a leading edge and a trailing edge to define a stream-wise direction, and between a root and a tip to define a span-wise direction, and a set of dimples provide on the outer wall of at least one of the airfoils, the set of dimples spaced in at least one of the stream-wise or span-wise directions.

Abstract: Aerodynamically mistuned airfoils for unsteady loss reductions are disclosed herein. An example apparatus disclosed herein includes a disk, a first airfoil coupled to the disk, the first airfoil having a first geometry, and a second airfoil coupled to the disk adjacent to the first airfoil, the second airfoil having a second geometry different than the first geometry, the first airfoil and the second airfoil produce non-uniform wake passing times during operation of the disk.

Abstract: A gas turbine engine comprising a set of circumferentially adjacent airfoils, the airfoils having an outer wall defining a pressure side and a suction side extending between a leading edge and a trailing edge to define a stream-wise direction, and between a root and a tip to define a span-wise direction, and a set of dimples provide on the outer wall of at least one of the airfoils, the set of dimples spaced in at least one of the stream-wise or span-wise directions.

Abstract: A method for determining a flow condition includes disposing a plurality of sensors on a surface and receiving a first sensor signal and a second sensor signal from the plurality of sensors. The method further includes determining at least one correlation parameter based on the first sensor signal and the second sensor signal. The method also includes receiving a plurality of stored parameters from a database, wherein each of the plurality of stored parameters is representative of a corresponding flow condition. The method also includes comparing the at least one correlation parameter with the plurality of stored parameters and selecting at least one matching stored parameter and determining a matching flow condition based on the at least one matching stored parameter.

Abstract: A method for reducing noise generated by a wind turbine includes measuring a reference temperature of the wind turbine. The method also includes regulating a trailing edge surface temperature of a trailing edge portion of a rotor blade attached to the wind turbine. In addition, the method includes measuring the trailing edge surface temperature. Further, the method includes regulating the trailing edge surface temperature to maintain a predetermined temperature differential between the reference temperature and the trailing edge surface temperature.

Abstract: A method for determining a flow condition includes disposing a plurality of sensors on a surface and receiving a first sensor signal and a second sensor signal from the plurality of sensors. The method further includes determining at least one correlation parameter based on the first sensor signal and the second sensor signal. The method also includes receiving a plurality of stored parameters from a database, wherein each of the plurality of stored parameters is representative of a corresponding flow condition. The method also includes comparing the at least one correlation parameter with the plurality of stored parameters and selecting at least one matching stored parameter and determining a matching flow condition based on the at least one matching stored parameter.

Abstract: A method for reducing noise generated by a wind turbine includes measuring a reference temperature of the wind turbine. The method also includes regulating a trailing edge surface temperature of a trailing edge portion of a rotor blade attached to the wind turbine. In addition, the method includes measuring the trailing edge surface temperature. Further, the method includes regulating the trailing edge surface temperature to maintain a predetermined temperature differential between the reference temperature and the trailing edge surface temperature.