TURBOFAN ENGINE SOUND CONTROL SYSTEM AND METHOD

摘要

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.