Dual purpose apparatus for turbine engine exhaust noise and anti- surge air noise reduction

摘要

In order to reduce turbine engine exhaust noise while simultaneously reducing anti-surge airflow noise, a combination noise reduction apparatus or tube (10) is provided having a series of holes (26) in its side. The tube (10) is in communication with a source of anti- surge air through an anti-surge air outlet (22) to be delivered into the exhaust airflow in an exhaust duct (12). The tube (10) diffuses the anti- surge air, shields the noise of the anti-surge air by dissipating the acoustic energy within the tube (10), and provides for an even distribution of the anti-surge air into the exhaust airflow. As a result, a temperature discontinuity is created in the exhaust duct (12) which results in an acoustic impedance that reflects acoustic noise back to the source of the noise.