Abstract: A fluid machine for an aircraft engine has: first and second walls; a gaspath defined between the first wall and the second wall; a rotor having blades rotatable about the central axis; and a stator having: a row of vanes having airfoils including leading edges, trailing edges, pressure sides and suction sides opposed the pressure sides, and depressions defined in the first wall, the depressions extending from a baseline surface of the first wall away from the second wall, a depression of the depressions located circumferentially between a pressure side of the pressure sides and a suction side of the suction sides, the depression axially overlapping the airfoils and located closer to the suction side than to the pressure side, an upstream end of the depression located closer to a leading edge of the leading edges than to a trailing edge of the trailing edges.

Abstract: A fluid machine for an aircraft engine has: first and second walls; a gaspath defined between the first wall and the second wall; a rotor having blades rotatable about the central axis; and a stator having: a row of vanes having airfoils including leading edges, trailing edges, pressure sides and suction sides opposed the pressure sides, and depressions defined in the first wall, the depressions extending from a baseline surface of the first wall away from the second wall, a depression of the depressions located circumferentially between a pressure side of the pressure sides and a suction side of the suction sides, the depression axially overlapping the airfoils and located closer to the suction side than to the pressure side, an upstream end of the depression located closer to a leading edge of the leading edges than to a trailing edge of the trailing edges.

Abstract: A fluid machine has: first and second walls; a gaspath defined between the first wall and the second wall; a rotor having blades rotatable about the central axis; and a stator having: a row of vanes having airfoils including leading edges, trailing edges, pressure sides and suction sides opposed the pressure sides, and depressions defined in the first wall, the depressions extending from a baseline surface of the first wall away from the second wall, a depression of the depressions located circumferentially between a pressure side of the pressure sides and a suction side of the suction sides, the depression axially overlapping the airfoils and extending in a downstream direction from an upstream end to a downstream end, the downstream end located closer to a trailing edge of the trailing edges than to a leading edge of the leading edges.

Abstract: A casing treatment for a compressor includes one or more cavities in a casing disposed radially outwardly of tips of the compressor rotor blades. A liner is moveable relative to the casing between a first position and a second position. The liner is shaped to add a volume to the tip clearance gap when moving from the second position toward the first position. The liner is displaceable between the first and second positions in coordination with at least the rotation of inlet guide vanes (IGVs) between IGV positions.

Abstract: A casing treatment for a compressor includes one or more cavities in a casing disposed radially outwardly of tips of the compressor rotor blades. A liner is moveable relative to the casing between a first position and a second position. The liner is shaped to add a volume to the tip clearance gap when moving from the second position toward the first position. The liner is displaceable between the first and second positions in coordination with at least the rotation of inlet guide vanes (IGVs) between IGV positions.

Abstract: There is disclosed a fan assembly including a fan rotor including a hub and fan blades. The fan blades have a leading edge and a trailing edge. A fan stator downstream of the fan rotor relative to a direction of an airflow through the fan assembly. The fan stator includes vanes extending between radially inner ends and radially outer ends. A flow recirculation circuit has an inlet downstream of the vanes of the fan stator and an outlet upstream of the vanes. A recirculation rotor has a plurality of airfoils circumferentially distributed around the axis and located in the flow recirculation circuit. The recirculation rotor is rotatable about the axis within the recirculation circuit. A method of operating the fan assembly is also disclosed.

Abstract: A gas turbine engine includes rotor having a hub, and a plurality of blades extending generally radially from the hub. Each of the blades has an airfoil portion. The airfoil portion has a leading edge and a trailing edge defining a chordwise direction, and a root and a tip defining a spanwise direction. Only a sub-set of the blades has a cutback at at least one of the trailing edge and the leading edge. A method of designing and a method of assembling a rotor having noise reduction properties in a gas turbine engine is also presented.

Abstract: A fluid machine has: first and second walls; a gaspath defined between the first wall and the second wall; a rotor having blades rotatable about the central axis; and a tandem having: a first row of first vanes having first airfoils including first leading edges, first trailing edges, first pressure sides and first suction sides opposed the first pressure sides, and a second row of second vanes downstream of the first vanes and having second airfoils including second leading edges, second trailing edges, second pressure sides and second suction sides opposed the second pressure sides, the first vanes being circumferentially offset from the second vanes; and depressions defined in the first wall, a depression of the depressions located circumferentially between a pressure side of the first pressure sides and a suction side of the second suction sides, the depressions axially overlapping the first airfoils and the second airfoils.

Abstract: A compressor diffuser for a gas turbine engine includes one or more diffuser pipes having a tubular body defining an internal flow passage extending therethrough. The tubular body includes a first portion extending in a first direction, a second portion extending in a second direction different from the first direction, and a curved portion fluidly linking the first portion and the second portion. A splitter vane is disposed within the internal flow passage of the curved portion of the tubular body, the splitter vane defining a convergent flow passage between itself and a radially inner wall of the curved portion, and a divergent flow passage between itself and a radially outer wall of the curved portion.

Abstract: A compressor has: a rotor and a stator having vanes, a vane of the vanes having an airfoil extending from a root proximate an inner hub to a radially outer tip, the airfoil having a leading edge, a trailing edge, and a chord extending between the leading edge and the trailing edge to define a chord length, the airfoil having a pressure side surface and a suction side surface, and a fillet disposed at the leading edge of the root of the airfoil and extending between the pressure side surface and the inner hub, the fillet having a radial height being maximum at the leading edge, the radial height decreasing from the leading edge to blend smoothly into a remainder of the airfoil, the fillet extending downstream from the leading edge a chord-wise distance of less than 50% of a chord length of the airfoil on the pressure side surface.

Abstract: A gas turbine engine includes rotor having a hub, and a plurality of blades extending generally radially from the hub. Each of the blades has an airfoil portion. The airfoil portion has a leading edge and a trailing edge defining a chordwise direction, and a root and a tip defining a spanwise direction. Only a sub-set of the blades has a cutback at at least one of the trailing edge and the leading edge. A method of designing and a method of assembling a rotor having noise reduction properties in a gas turbine engine is also presented.

Abstract: A compressor of a gas turbine engine includes a rotor and a stator located downstream of the rotor. The stator has a plurality of vanes each with an airfoil extending span-wise between a root proximate an inner hub of the stator and a tip. A fillet is disposed at the leading edge of the root of the airfoil, and extends between a pressure side surface of the airfoil and the inner hub.

Abstract: A gas turbine engine includes rotor having a hub, and a plurality of blades extending generally radially from the hub. Each of the blades has an airfoil portion. The airfoil portion has a leading edge and a trailing edge defining a chordwise direction, and a root and a tip defining a spanwise direction. Only a sub-set of the blades has a cutback at at least one of the trailing edge and the leading edge. A method of designing and a method of assembling a rotor having noise reduction properties in a gas turbine engine is also presented.

Abstract: A compressor diffuser for a gas turbine engine includes one or more diffuser pipes having a tubular body defining an internal flow passage extending therethrough. The tubular body includes a first portion extending in a first direction, a second portion extending in a second direction different from the first direction, and a curved portion fluidly linking the first portion and the second portion. A splitter vane is disposed within the internal flow passage of the curved portion of the tubular body, the splitter vane defining a convergent flow passage between itself and a radially inner wall of the curved portion, and a divergent flow passage between itself and a radially outer wall of the curved portion.

Abstract: There is disclosed a fan assembly including a fan rotor including a hub and fan blades. The fan blades have a leading edge and a trailing edge. A fan stator downstream of the fan rotor relative to a direction of an airflow through the fan assembly. The fan stator includes vanes extending between radially inner ends and radially outer ends. A flow recirculation circuit has an inlet downstream of radially inner ends of the vanes of the fan stator and an outlet upstream of radially inner ends of the vanes. A recirculation stator has a plurality of stationary guide vanes circumferentially distributed around the axis and located in the flow recirculation circuit between the inlet and the outlet A method of operating the fan assembly is also disclosed.

Abstract: A method of operating a compressor of a gas turbine engine is described which includes directing a main airflow through tandem stator rows in a gaspath of the compressor, extracting a first portion of the main airflow from a first location proximate radially inner roots of stators of the first or second stator rows, extracting a second portion of the main airflow from a second location proximate the radially inner roots of the stators of the first or second stator rows, the second location being downstream of the first location relative to the main airflow, and re-injecting the combined extracted flow back into the main airflow at a third location. The third location is located upstream of the first and second locations, and is upstream of a leading edge of stators of the first stator row.

Abstract: A vane diffuser for diffusing gases is disclosed. The diffuser has an annular diffuser body including a plurality of diffuser vanes defining diffuser passages. The diffuser passages are circumferentially distributed. A direction of main gas flow through the diffuser passages is defined from a passage inlet in fluid communication with the outlet of the compressor to a passage outlet. A plurality of fluid injection conduits each extend between a conduit inlet and a conduit outlet for at least one of the diffuser vanes. The conduit outlet defines at least one opening in at least one of the pressure and suction side surfaces and is configured to inject fluid along one of the pressure and suction side surfaces in the direction of main gas flow through the corresponding diffuser passage.

Abstract: A method of operating a compressor of a gas turbine engine is described which includes directing a main airflow through tandem stator rows in a gaspath of the compressor, extracting a first portion of the main airflow from a first location proximate radially inner roots of stators of the first or second stator rows, extracting a second portion of the main airflow from a second location proximate the radially inner roots of the stators of the first or second stator rows, the second location being downstream of the first location relative to the main airflow, and re-injecting the combined extracted flow back into the main airflow at a third location. The third location is located upstream of the first and second locations, and is upstream of a leading edge of stators of the first stator row.

Abstract: A rotor for a gas turbine engine includes a plurality of radially extending blades, each having a remote blade tip defining an outer tip surface, and a leading edge defined between opposed pressure and suction side airfoil surfaces. A shroud circumferentially surrounds the rotor, and a radial distance between an inner surface of the shroud and the outer tip surface of the blades defines a radial tip clearance gap therebetween. The tip of each of the blades has a pressure side edge formed at the intersection between the outer tip surface and the pressure side airfoil surface, and a suction side edge formed at the intersection between the outer tip surface and the pressure side airfoil surface. The suction side edge has a larger radius of curvature than the pressure side edge, thereby reducing the amount of tip leakage flow through the radial tip clearance gap.

Abstract: There is disclosed a fan assembly including a fan rotor including a hub and fan blades. The fan blades have a leading edge and a trailing edge. A fan stator downstream of the fan rotor relative to a direction of an airflow through the fan assembly. The fan stator includes vanes extending between radially inner ends and radially outer ends. A flow recirculation circuit has an inlet downstream of the vanes of the fan stator and an outlet upstream of the vanes. A recirculation rotor has a plurality of airfoils circumferentially distributed around the axis and located in the flow recirculation circuit. The recirculation rotor is rotatable about the axis within the recirculation circuit. A method of operating the fan assembly is also disclosed.