US Patent 9062610 Exhaust cone

A gas turbine engine exhaust cone (40) comprising one or more acoustic absorption chambers (48), each chamber (48) comprising two side walls (50) and an acoustic attenuation wall (62). The side walls (50) define the circumferential extent of the chamber (48). The acoustic attenuation wall (62) has one or more acoustic attenuators (64) and is positioned circumferentially intermediate the side walls (50). The side walls (50) extend axially along the exhaust cone (40) at least one of them with a circumferential progression. The acoustic attenuation wall (62) extends axially along the exhaust cone (40) with or without a circumferential progression.