Abstract: A fan assembly for a gas turbine engine is described which includes a fan and a leading edge assembly mounted to the fan. The leading edge assembly includes a plurality of leading edge extensions projecting from a central core and circumferentially spaced apart to align with leading edges of the fan blades. The leading edge extensions define cavities between the leading edges and the extensions. The cavities extend radially at least partially within the leading edge extensions, and receive heated pressurized air from the engine in operation. Elongated slots extend radially along a downstream edge of the leading edge extensions, and are defined axially between the downstream edge and the leading edges of the blades. The slots provide fluid flow communication between the cavities and at least pressure surfaces of the fan blades.

Abstract: A fan nose cone is disclosed for impeding icing and recovering momentum in a gas turbine engine. The fan nose cone comprises: an axially symmetric shell having a convex external surface and an internal surface, the shell having an opening in a forward end of the shell for communication with a source of heated pressurized air; and an axially symmetric deflector disposed forward of the opening, the deflector being configured to direct heated pressurized air exiting from the opening radially outwardly to flow in a downstream direction over the convex external surface of the shell during operation. The shell of the fan nose cone may have a rearward circumferential vent in communication with the source of heated pressurized air for directing heated pressurized from the vent in a radially outward and downstream direction toward the fan blade platforms.

Abstract: A fan assembly for a gas turbine engine is described which includes a fan and a leading edge assembly mounted to the fan. The leading edge assembly includes a plurality of leading edge extensions projecting from a central core and circumferentially spaced apart to align with leading edges of the fan blades. The leading edge extensions define cavities between the leading edges and the extensions. The cavities extend radially at least partially within the leading edge extensions, and receive heated pressurized air from the engine in operation. Elongated slots extend radially along a downstream edge of the leading edge extensions, and are defined axially between the downstream edge and the leading edges of the blades. The slots provide fluid flow communication between the cavities and at least pressure surfaces of the fan blades.

Abstract: A duct for a gas turbine engine, the duct has a wall defining a flow passage for an airflow, the wall defining a baseline surface, the duct comprising an off-take port for drawing a portion of the airflow out of the duct, the off-take port including a projected portion projecting away from the baseline surface into the flow passage, a conduit opening defined within the projected portion for receiving the portion of the airflow, and an off-take conduit communicating with the conduit opening for directing the portion of the airflow away from the duct, the projected portion having a hump upstream of the conduit opening relative to a direction of the airflow and a scoop downstream of the opening relative to the direction of the airflow.

Abstract: A bearing chamber configuration that favorably directs the flow of oil/air mixture inside the bearing chamber of a gas turbine engine is disclosed. The bearing chamber includes an annular baffle surrounding a rotatable shaft. The baffle comprises an annular groove facing radially inwardly and a first radially-inner annular surface extending axially from a first side of the annular groove. The first radially-inner annular surface of the baffle cooperating with the shaft to define a first space inside the bearing chamber and adjacent the seal. The first space is circumferentially uniform.

Abstract: A TOBI assembly including a TOBI having a body adapted to be fixed to a stator assembly and defining an annular passageway to receive cooling air, and defining a plurality of discharge nozzles. A back plate configured to be mounted to a rotor assembly to rotate therewith. The back plate has an axial portion spaced radially inwardly from the plurality of discharge nozzles. The axial portion has radially-spaced outer and inner walls defining an annular flow transition chamber. The flow transition chamber has a radial segment extending radially inwardly from an inlet opening communicating with the discharge nozzles, and an axial segment extending axially from the radial segment to an outlet opening configured to deliver the cooling air to a rotor assembly.

Abstract: A bearing chamber configuration that favorably directs the flow of oil/air mixture inside the bearing chamber of a gas turbine engine is disclosed. The bearing chamber includes an annular baffle surrounding a rotatable shaft. The baffle comprises an annular groove facing radially inwardly and a first radially-inner annular surface extending axially from a first side of the annular groove. The first radially-inner annular surface of the baffle cooperating with the shaft to define a first space inside the bearing chamber and adjacent the seal. The first space is circumferentially uniform.

Abstract: A fan nose cone is disclosed for impeding icing and recovering momentum in a gas turbine engine. The fan nose cone comprises: an axially symmetric shell having a convex external surface and an internal surface, the shell having an opening in a forward end of the shell for communication with a source of heated pressurized air; and an axially symmetric deflector disposed forward of the opening, the deflector being configured to direct heated pressurized air exiting from the opening radially outwardly to flow in a downstream direction over the convex external surface of the shell during operation. The shell of the fan nose cone may have a rearward circumferential vent in communication with the source of heated pressurized air for directing heated pressurized from the vent in a radially outward and downstream direction toward the fan blade platforms.