A gas turbine engine including an engine core with a duct, nacelle, and bypass duct receiving fan-accelerated bypass air flow. The core duct is located radially inside the bypass duct and receives the core air flow. A housing between the core and bypass ducts has an outer wall, which is the bypass duct inner wall, and inner wall which is core duct outer wall. The housing extends axially from the gas turbine engine, and splits fan accelerated air flow axially forward into the bypass and core ducts. At least two heat exchangers for cooling engine based oil are mounted in the housing. A flow passage inside the housing delivers air flow to the heat exchangers, and returns air flow from the heat exchangers. The at least two heat exchangers extend circumferentially, and a flow divider is between the heat exchanger ends and diverts air flow to the heat exchangers.

A gas turbine engine including an engine core with a duct, nacelle, and bypass duct receiving fan-accelerated bypass air flow. The core duct is located radially inside the bypass duct and receives the core air flow. A housing between the core and bypass ducts has an outer wall, which is the bypass duct inner wall, and inner wall which is core duct outer wall. The housing extends axially from the gas turbine engine, and splits fan accelerated air flow axially forward into the bypass and core ducts. At least two heat exchangers for cooling engine based oil are mounted in the housing. A flow passage inside the housing delivers air flow to the heat exchangers, and returns air flow from the heat exchangers. The at least two heat exchangers extend circumferentially, and a flow divider is between the heat exchanger ends and diverts air flow to the heat exchangers.

An oil tank for a gas turbine engine is provided. The oil tank includes an oil cavity defined within structural walls of a nacelle of the gas turbine engine, the oil cavity having an oil inlet and an oil outlet. At least one of the structural walls has an interior side facing the oil cavity and an exterior side. The interior side includes a plurality of upstanding protrusions extending into the oil cavity and fully immersed in oil when the gas turbine engine is in use during steady state operation. The exterior side includes a plurality of fins extending therefrom and exposed to an ambient air stream during steady state operation of the gas turbine engine.

An oil tank for a gas turbine engine is provided. The oil tank includes an oil cavity defined within structural walls of a nacelle of the gas turbine engine, the oil cavity having an oil inlet and an oil outlet. At least one of the structural walls has an interior side facing the oil cavity and an exterior side. The interior side includes a plurality of upstanding protrusions extending into the oil cavity and fully immersed in oil when the gas turbine engine is in use during steady state operation. The exterior side includes a plurality of fins extending therefrom and exposed to an ambient air stream during steady state operation of the gas turbine engine.

There are provided a throttle mechanism and the like that are capable of easily changing a cross-sectional area of a flow path according to an operating state. The throttle mechanism in an embodiment is a throttle mechanism that controls a flow rate of a fluid flowing through a flow path, and is configured to make a cross-sectional area of the flow path change autonomously according to temperature.

There are provided a throttle mechanism and the like that are capable of easily changing a cross-sectional area of a flow path according to an operating state. The throttle mechanism in an embodiment is a throttle mechanism that controls a flow rate of a fluid flowing through a flow path, and is configured to make a cross-sectional area of the flow path change autonomously according to temperature.

A secondary air system (SAS) of an aircraft engine that produces secondary airflow from a source of secondary air includes a hollow strut and one or more SAS feed pipes upstream thereof. The hollow strut extends radially through the main gas path of the engine and defines therein a strut conduit extending between a strut inlet and a strut outlet at opposite ends of the hollow strut. The strut outlet is in fluid flow communication with a buffer cavity for feeding the secondary airflow to the engine core. The SAS feed pipe includes an inlet receiving the secondary airflow from the source of secondary air, and an outlet in fluid flow communication with the strut inlet to feed the secondary airflow into the strut conduit. The SAS feed pipe has a sonic orifice therein, between the inlet and the outlet thereof.

A secondary air system (SAS) of an aircraft engine that produces secondary airflow from a source of secondary air includes a hollow strut and one or more SAS feed pipes upstream thereof. The hollow strut extends radially through the main gas path of the engine and defines therein a strut conduit extending between a strut inlet and a strut outlet at opposite ends of the hollow strut. The strut outlet is in fluid flow communication with a buffer cavity for feeding the secondary airflow to the engine core. The SAS feed pipe includes an inlet receiving the secondary airflow from the source of secondary air, and an outlet in fluid flow communication with the strut inlet to feed the secondary airflow into the strut conduit. The SAS feed pipe has a sonic orifice therein, between the inlet and the outlet thereof.

The gas turbine engine can have an air mover configured for generating a flow of air around a rotation axis; a surface extending around the rotation axis delimiting a passage for the flow of air downstream of the air mover; an electric machine disposed within the passage and coupled to the air mover; a coolant circuit having: an evaporator circumferentially disposed around at least part of the electric machine and in thermal communication therewith; a condenser having a surface cooler circumferentially disposed at least partially around the surface and in thermal communication therewith; a first conduit fluidly connecting an upper region of the evaporator to an upper region of the condenser; and a second conduit fluidly connecting a lower region of the condenser to a lower region of the evaporator; and a coolant fluid in the coolant circuit.

A gas turbine engine includes a compressor section, a combustor section, and a turbine section operably coupled to the compressor section. A primary flow path is defined through the compressor section, the combustor section, and the turbine section. An engine case surrounds the compressor section, the combustor section, and the turbine section. The gas turbine engine also includes a means for providing an active variable cooling flow through a bypass duct external to the engine case to a secondary flow cavity of the turbine section.