A boundary layer turbomachine (100) can include a housing (110) defining an interior space (115) and having an inlet opening (112) and an outlet (113) opening to facilitate movement of a fluid through the housing (110). The boundary layer turbomachine (100) can also include a rotor assembly (120) disposed in the rotor chamber (117) and configured to rotate about an axis of rotation (101). The rotor assembly (120) can have a plurality of disks (121) spaced apart along the axis of rotation (101) and defining an interior opening along the axis of rotation (101). The fluid can pass through gaps between the disks (121) and the interior opening as the fluid moves through the housing (110). Corresponding rotor assembly and partition are also provided.

A gas turbine engine comprises a main compressor section having a downstream most end, and more upstream locations. A turbine section has a high pressure turbine. A tap taps air from at least one of the more upstream locations in the compressor section, passes the tapped air through a heat exchanger and then to a cooling compressor. The cooling compressor compresses cooling air downstream of the heat exchanger, and delivers air into the high pressure turbine. The heat exchanger has at least two passes, with one of the passes passing air radially outwardly, and a second of the passes returning the air radially inwardly to the compressor. An intercooling system for a gas turbine engine is also disclosed.

A turbine-tip clearance control system offtake for a gas turbine engine, comprising: an air input duct in fluid communication with a compressor bleed air outlet, the air input duct comprising an exit aperture, the exit aperture defining an exit flow path for at least a portion of the air flowing in the air input duct during use of the gas turbine engine. The direction of airflow through the exit aperture, during use of the gas turbine engine, has at least a component that is anti-parallel to the direction of airflow in the air input duct in a region of the air input duct adjacent to the exit aperture. A turbine-tip clearance control system, a gas turbine engine for an aircraft and a method of supplying airflow to a turbine-tip clearance control system in a gas turbine engine are also disclosed.

A gas turbine engine includes a core engine casing and a bypass duct defined between a nacelle and the core engine casing. The gas turbine engine further includes a plurality of diverter fences pivotally coupled to the core engine casing. Each diverter fence is pivotable relative to the core engine casing about a pivot axis, which is circumferentially and obliquely inclined with respect to a principal rotational axis. Each diverter fence is configured to move between a first position in which an outboard edge is disposed adjacent to a casing outer surface, and a second position in which the outboard edge is radially spaced apart from the casing outer surface, such that each diverter fence radially extends outwards from the casing outer surface into the bypass duct.

A gas turbine engine includes a main compressor. A tap is fluidly connected downstream of the main compressor. A heat exchanger is fluidly connected downstream of the tap. An auxiliary compressor unit is fluidly connected downstream of the heat exchanger. The auxiliary compressor unit is configured to compress air cooled by the heat exchanger with an overall auxiliary compressor unit pressure ratio between 1.1 and 6.0. An intercooling system for a gas turbine engine is also disclosed.

The present application provides a purge flow delivery system that may be used with a gas turbine engine. The purge flow delivery system may include a mixing chamber with a first sidewall, a second sidewall, and a cover plate, a first inlet tube positioned about the first sidewall, the first inlet tube configured to deliver a first fluid to the mixing chamber, a second inlet tube positioned about the second sidewall, the second inlet tube configured to deliver a second fluid to the mixing chamber, and a baffle plate attached to the cover plate and positioned to direct the first fluid at a first angle and the second fluid at a second angle.

A gas turbine engine comprises a main compressor section having a downstream most end, and more upstream locations. A turbine section has a high pressure turbine. A tap taps air from at least one of the more upstream locations in the compressor section, passes the tapped air through a heat exchanger and then to a cooling compressor. The cooling compressor compresses ng air downstream of the heat exchanger, and delivers air into the high pressure turbine. The heat exchanger has at least two passes, with one of the passes passing air radially outwardly, and a second of the passes returning the air radially inwardly to the compressor. An intercooling system for a gas turbine engine is also disclosed.

Systems and methods for adjusting airflow distortion in a gas turbine engine using a secondary airflow passage assembly are disclosed. A gas turbine engine can include a compressor section, a combustion section, and a turbine section in series flow and defining at least in part an engine airflow path. A casing can enclose the gas turbine engine and be at least partially exposed to a bypass airflow. The gas turbine engine can further include a secondary airflow passage assembly comprising a door and a duct, the duct defining an inlet located on the casing, the duct defining an outlet in airflow communication with the engine airflow path, the duct comprising an airflow passage extending between the inlet and outlet. The door can be moveable between an open and closed position to allow a portion of the bypass airflow to flow through the airflow passage to adjust airflow distortion.

The present application provides a purge flow delivery system that may be used with a gas turbine engine. The purge flow delivery system may include a mixing chamber with a first sidewall, a second sidewall, and a cover plate, a first inlet tube positioned about the first sidewall, the first inlet tube configured to deliver a first fluid to the mixing chamber, a second inlet tube positioned about the second sidewall, the second inlet tube configured to deliver a second fluid to the mixing chamber, and a baffle plate attached to the cover plate and positioned to direct the first fluid at a first angle and the second fluid at a second angle.

A gas turbine engine according to the present disclosure includes a first compressor and a first turbine for driving the first compressor. A core section includes a second compressor and a second turbine for driving the second compressor. A third turbine is arranged fluidly downstream of the first turbine and the second turbine and configured to drive a power take-off. A first duct system is arranged fluidly between the low-pressure compressor and the core section. The first duct system is arranged to reverse fluid flow before entry into the core section.