Active cooling of the environment surrounding the outer casing of the gas turbine for the release of air near the exhaust stream With pressure below ambient pressure

摘要

A gas turbine engine including an outer case extending circumferentially around the central longitudinal axis. A cooling channel is associated with the outer surface of the outer case, the cooling channel having a channel inlet and a channel outlet. An air duct is provided including an inlet end in fluid communication with the channel outlet and an outlet end in fluid communication with an exhaust gas flow from a turbine section of the gas turbine engine. An exit structure is located at the air duct outlet end, and the exit structure provides a sub-ambient pressure at the air duct outlet end to induce a flow from the air duct inlet end to the air duct outlet end.