Abstract: A gas turbine engine includes a controller that controls a fan blade flutter characteristic through control of a variable area fan nozzle.

Abstract: An example turbofan engine sound control system includes a core nacelle (12) housing a compressor and a turbine. The core nacelle is disposed within a fan nacelle (34). The fan nacelle includes a turbofan. A bypass flow path downstream from the turbofan is arranged between the two nacelles. A controller (50) is programmed to manipulate the nozzle exit area to control sound propagating from the engine. In one example, the controller manipulates the nozzle exit area using hinged flaps (42) to control engine sound. The hinged flaps open and close to adjust the nozzle exit area and the associated bypass flow rate.

Abstract: A gas turbine engine includes a controller that controls a fan blade flutter characteristic through control of a variable area fan nozzle.

Abstract: A system and method of controlling a fan blade flutter characteristic of a gas turbine engine includes adjusting a variable area fan nozzle in response to a neural network.

Abstract: A turbine engine provides a spool supporting a turbine. The spool is arranged in a core nacelle and includes a thrust bearing. A fan is arranged upstream from the core nacelle and is coupled to the spool. A fan nacelle surrounds the fan and core nacelle and provides a bypass flow path that includes a fan nozzle exit area. A flow control device is adapted to effectively change the fan nozzle exit area. A controller is programmed to monitor the thrust bearing and command the flow control device in response to an undesired load on the thrust bearing. Effectively changing the fan nozzle exit area with the flow control device actively manages the bearing thrust load to desired levels.

Abstract: A turbine engine provides a spool supporting a turbine. The spool is arranged in a core nacelle and includes a thrust bearing. A fan is arranged upstream from the core nacelle and is coupled to the spool. A fan nacelle surrounds the fan and core nacelle and provides a bypass flow path that includes a fan nozzle exit area. A flow control device is adapted to effectively change the fan nozzle exit area. A controller is programmed to monitor the thrust bearing and command the flow control device in response to an undesired load on the thrust bearing. Effectively changing the fan nozzle exit area with the flow control device actively manages the bearing thrust load to desired levels.

Abstract: A turbine engine provides a spool supporting a turbine. The spool is arranged in a core nacelle and includes a thrust bearing. A fan is arranged upstream from the core nacelle and is coupled to the spool. A fan nacelle surrounds the fan and core nacelle and provides a bypass flow path that includes a fan nozzle exit area. A flow control device is adapted to effectively change the fan nozzle exit area. A controller is programmed to monitor the thrust bearing and command the flow control device in response to an undesired load on the thrust bearing. Effectively changing the fan nozzle exit area with the flow control device actively manages the bearing thrust load to desired levels.

Abstract: A turbofan engine is provided that includes a fan nacelle surrounding a core nacelle. The core nacelle houses a spool. The fan and core nacelles provide a bypass flow path having a nozzle exit area. A turbofan is arranged within the fan nacelle upstream from the core nacelle. A flow control device is adapted to effectively change the nozzle exit area to obtain a desired operating condition for the turbofan engine. A gear train couples the spool and turbofan for reducing a turbofan rotational speed relative to a spool rotational speed. A controller is programmed to respond to at least one sensor. The controller is programmed to effectively control the nozzle area.

Abstract: An example turbofan engine sound control system includes a core nacelle (12) housing a compressor and a turbine. The core nacelle is disposed within a fan nacelle (34). The fan nacelle includes a turbofan. A bypass flow path downstream from the turbofan is arranged between the two nacelles. A controller (50) is programmed to manipulate the nozzle exit area to control sound propagating from the engine. In one example, the controller manipulates the nozzle exit area using hinged flaps (42) to control engine sound. The hinged flaps open and close to adjust the nozzle exit area and the associated bypass flow rate.

Abstract: A system and method of controlling a fan blade flutter characteristic of a gas turbine engine includes adjusting a variable area fan nozzle in response to a neural network.

Abstract: A turbine engine provides a spool supporting a turbine. The spool is arranged in a core nacelle and includes a thrust bearing. A fan is arranged upstream from the core nacelle and is coupled to the spool. A fan nacelle surrounds the fan and core nacelle and provides a bypass flow path that includes a fan nozzle exit area. A flow control device is adapted to effectively change the fan nozzle exit area. A controller is programmed to monitor the thrust bearing and command the flow control device in response to an undesired load on the thrust bearing. Effectively changing the fan nozzle exit area with the flow control device actively manages the bearing thrust load to desired levels.