An air intake system (AIS) has a plenum and an inlet barrier filter associated with the plenum, through which air can selectively enter the plenum. The AIS also has an inlet duct associated with the plenum, through which air can selectively enter the plenum. The AIS also has a bypass door associated with the inlet duct, the bypass door being configured to selectively change an amount of air allowed to pass through the inlet duct. The AIS also has a filter airflow change device configured to change an amount of airflow allowed through the inlet barrier filter.

There is disclosed an inertial particle separator communicating with an engine inlet. The inertial particle separator has: a main duct body; a bypass duct; and a splitter defined by an intersection of the main duct and the bypass duct. The main duct and the bypass duct having particular geometric characteristics. A method of separating particles via inertia in an aircraft engine inlet is also provided.

Air filtration assemblies configured to provide instant detection of particles and/or improve particle filtration are disclosed. The assemblies may include an air inlet duct in fluid communication with a compressor of a gas turbine system. The air inlet duct may include an inlet for receiving intake air including intake air particles, and an outlet positioned opposite the inlet. The assembly may also include a plurality of vane filters at the inlet, an array of fabric filters positioned in the air inlet duct, downstream of the vane filters, and a silencer assembly positioned in the air inlet duct, downstream of the fabric filters. Additionally, the assembly may include an electrostatic component positioned in the air inlet duct, downstream of the fabric filters. The electrostatic component may be configured to charge the intake air particles that pass through the vane filters and the fabric filters.

An aircraft includes a fuselage, an engine exhaust port extending through the fuselage, an air intake extending through the fuselage forward from, and adjacent to, the engine exhaust port, and an air cleaning assembly positioned over the air intake. The aircraft also includes a pressure recovery device including an outer wall positioned above the air cleaning assembly. A distance from a forward edge of the outer wall to the air cleaning assembly is greater than a distance from an aft edge of the outer wall to the air cleaning assembly. An inlet flow axis is defined normal to a cross-sectional flow area of the pressure recovery device at the forward edge, and is oriented upward at an acute angle relative to a longitudinal axis of the aircraft.

A control system for controlling a shut-off valve of an aircraft. The shut-off valve is configured to open a bypass circuit that is initially closed. This circuit makes it possible to feed air to an aircraft engine without going via an air filter associated with an air intake. The control system comprises: a manual control member for controlling the shut-off valve, this member being actuatable manually so as to cause the bypass circuit to open; and a computer configured to compute a current value of a level of clogging TC of an air filter. The control system further comprises a comparator for comparing the current value of the level of clogging TC with a first threshold value TC1 and with a second threshold value TC2, and an alerter for generating a first sensory signal and a second sensory signal.

An adaptive inertial particle separation system may include an active configuration and a passive configuration. The system may comprise an air-intake duct including an outer wall spaced apart from a central axis, an inner wall located between the outer wall and the engine rotation axis, an intake passage defined in part by the inner wall and the outer wall, and a splitter located between the outer wall and the inner wall. The system may further include a sensor operatively connected to the air-intake duct and operative to initiate at least one of the active configuration and passive configuration.

A centrifugal separator for removing particles from a fluid stream includes an angular velocity increaser configured to increase the angular velocity of a fluid stream, a flow splitter configured to split the fluid stream to form a concentrated-particle stream and a reduced-particle stream, and an exit conduit configured to receive the reduced-particle stream. An inducer assembly for a turbine engine includes an inducer with a flow passage having an inducer inlet and an inducer outlet in fluid communication with a turbine section of the engine, and a particle separator, which includes a particle concentrator that receives a compressed stream from a compressor section of the engine and a flow splitter. A turbine engine includes a cooling air flow circuit which supplies a fluid stream to a turbine section of the engine for cooling, a particle separator located within the cooling air flow circuit, and an inducer forming a portion of the cooling air flow circuit in fluid communication with the particle separator. A method of cooling a rotating blade of a turbine engine having an inducer includes directing a cooling fluid stream from a portion of turbine engine toward the rotating blade, separating particles from the cooling fluid stream by passing the cooling fluid stream through a inertial separator, accelerating a reduced-particle stream emitted from the inertial separator to the speed of the rotating blade, and orienting the reduced-particle stream by emitting the reduced-particle stream from the inertial separator into a cooling passage in the inducer.

A particle separator includes a housing through which a flow stream is directed. A number of guide vanes are disposed in the housing. The guide vanes have a profile wherein the flow stream is guided to follow the profile. The guide vanes have a wall surrounding an open interior that defines a vane plenum. A plurality of through-holes extend through the wall of the guide vane. The through-holes are open to the flow stream and to the vane plenum. A duct connects with the vane plenum and is configured to discharge particles collected in the vane plenum.

An air intake unit for an engine of an aircraft; the intake unit has: a tubular housing; a first inlet opening which is obtained through an outer wall of the tubular housing and through which external air can be taken in; an air filter which engages the first inlet opening; a second inlet opening which is obtained through the outer wall of the tubular housing and through which external air can be taken in; a shutter device which is coupled to the second inlet opening and is movable between a closed position, in which it closes the second inlet opening, and an open position, in which it sets the passage through the second inlet opening free; and an actuator, which moves the shutter device.

A turbomachine of the open rotor type or a turboprop engine comprises a nacelle defining an air inlet, a central hub and an annular air intake section surrounding the central hub and opening into a air supply main section, with the central hub comprising a central trap having an aperture for trapping the foreign objects in an air flow entering the turbomachine, and an air recovery channel having a discharge end, through which said air recovery channel opens into the main section, is provided on the central hub.