Both air duct inlet silencers and air duct outlet silencers for use with a
stationary gas turbine are disclosed. The sound attenuating duct unit
suitable for connecting to an outlet of a stationary gas turbine includes
a housing having a horizontal housing section and a vertical housing
section and having sidewalls surrounding a main airflow passageway that
extends along a substantial bend. An air inlet is located at one end of
the horizontal housing section and is adapted for connection to the outlet
of the gas turbine. Preferably two air outlets are located proximate to an
upper end of the vertical housing section. Splitters are mounted in the
housing, and they divide sections of the main airflow passageway into
smaller air passageways. At least one of the splitters is positioned
upstream in the main airflow passageway relative to other splitters. The
splitters contain sound attenuating material capable of withstanding
airflow temperatures in the main airflow passageway of at least 500
degrees Celsius. At least a substantial portion of both the sidewalls
surrounding the main airflow passageway and metal sidewalls forming the
splitters are made of perforated sheet metal.
