Abstract: A centrifugal compressor and a method of operating a centrifugal compressor. The centrifugal compressor includes: an impeller configured to suction a gas to be compressed; a diffuser disposed downstream of the impeller to pressurize the gas, the diffuser comprising a movable ring, a main passage in which the gas flows past the ring, and an openable branch passage; and a circulation loop comprising an inlet and an outlet, the outlet being in communication with an inlet of the impeller; the branch passage is disposed to be in communication with the main passage and the circulation loop when the ring moves into the main passage so that a portion of the gas in the main passage passes through the circulation loop and returns to the impeller so as to be suctioned, and to be closed when the ring is withdrawn from the main passage.

Abstract: A structure adapted to traverse a fluid environment exerting an ambient fluid pressure is provided. The structure includes an elongate body extending from a root to a wingtip and encapsulating at least one interior volume containing an interior fluid exerting an interior fluid pressure that is different from the ambient fluid pressure. A method of retrofitting a structure adapted to traverse a fluid environment exerting an ambient fluid pressure, the structure comprising an elongate body extending from a root to a wingtip and having at least one interior volume is also provided. The method includes sealing the elongate body to encapsulate the at least one interior volume containing an interior fluid; associating at least one valve with the at least one interior volume; and modifying interior fluid content via the at least one valve to produce an interior fluid pressure that is different from the ambient fluid pressure.

Abstract: According to the present teachings, an aircraft engine configured to controllably shed ice during icing conditions is presented. The engine has a member operating at a first angular velocity having a surface divided into a first ice accumulating surface configured to collect ice, and a first shadow surface configured to resist the collection of ice. A first flange is disposed between the first ice accumulating surface and the first shadow surface.

Abstract: A polymer airfoil assembly is disclosed and includes at least one cooling passage for circulating coolant to remove heat from the polymer airfoil portion.

Abstract: A fan module including variable-pitch blades, a fan rotor bearing the blades of the fan, each mounted to pivot about a pitch axis; a fan shaft extending along a longitudinal axis X inside the fan rotor and driving the fan rotor in rotation. A power shaft drives the fan shaft with a planetary gear speed reducer At least a first and a second bearing guide the rotation of the fan rotor, housed inside a lubrication chamber. A system varies the pitch of the fan blades, including a connecting mechanism connected to the blades of the fan and a controller acting on the connecting mechanism. The first bearing is disposed upstream of the speed reducer and the second bearing is disposed downstream of the speed reducer. The fan rotor is connected to the fan shaft by an annular trunnion extending at least along an upstream portion of the lubrication chamber.

Abstract: A propeller blade includes a body configured to extend radially from the hub of a propeller. The body can include a front surface, a back surface, a leading edge, and a trailing edge. The top of the body can form a tippet that generally transitions the front and back surfaces from extending in a generally radial direction to a generally axial direction. The tippet can reduce radial flow and force losses, redirect the radial flow in an axial direction, reduce the exit flow area of the propeller, and increase the inlet flow area of the propeller. The front surface of the blade can have a planar configuration that prevents or reduces the creation of low or negative pressure across the front surface of the blade and associated cavitation.

Abstract: A jacket ring assembly for a turbomachine, the jacket ring assembly including a casing part, a jacket ring segment which is adapted to radially outwardly surround a rotor blade ring and to this end is disposed radially inwardly of the casing part, as considered with respect to a longitudinal axis of the turbomachine, and a segmented ring which is circumferentially divided into segments and by which the jacket ring segment is mounted to the casing part, the segmented ring being axially form-fittingly disposed on a form-fitting element of the casing part, for which purpose each of the respective segments of the segmented ring is radially outwardly assembled with the form-fitting element, and the segmented ring forming a supporting seat on which the jacket ring segment is seated and radially inwardly supported with an axially forward end.

Abstract: A turbine engine with at least a compressor section, combustor section, turbine section and a set of airfoils. The airfoils include geometric characteristics to create a high contraction ratio (CR), a low blade turning (BT) at a radially inward location the airfoil, a low solidity, or a low aspect ratio (AR).

Abstract: A turbine for a turbo-machine is proposed in which, at a gas inlet for a turbine wheel, vanes extend from a nozzle ring though slots in a shroud. The vanes are formed with a leading portion which is arranged to contact a leading portion of a corresponding slot, and a trailing portion which is shaped, when the leading portion of the vane and slot are together, to be spaced from a corresponding trailing portion of the slot with a substantially constant spacing at room temperature. The contact may be a point contact, e.g. close to the leading edge of the vane. Alternatively, the vane may include a leading surface portion which conforms closely with the shape of a corresponding leading surface portion of one of the slots.

Abstract: Variable stator vanes with anti-lock trunnions are disclosed. An example apparatus disclosed herein includes an airfoil to be disposed within a flow path of a gas turbine engine, the gas turbine engine defining an axial axis, a radial axis and a circumferential axis, an outer trunnion, and an inner trunnion including a curved surface in an axial-radial plane, the inner trunnion enabling the airfoil to be rotatably mounted to an inner shroud of the gas turbine engine.

Abstract: A compressor section for a gas turbine engine according to an example of the present disclosure includes, among other things, a low pressure compressor including a plurality of rotor blades arranged about an axis, a high pressure compressor, and a core flowpath passing through the low pressure compressor. The core flowpath at the low pressure compressor defines an inner diameter and an outer diameter relative to the axis. The outer diameter has a slope angle relative to the axis.

Abstract: A rotor for a fluid machine includes a wheel that is supported for rotation about an axis of rotation. The wheel includes a back wall with an outer rim edge. The rotor also includes a plurality of blades that are attached to the back wall and that are spaced apart about the axis of rotation. Moreover, the rotor includes an inter-blade area on the back wall between neighboring ones of the plurality of blades. Furthermore, the rotor includes a balancing feature that is included in the inter-blade area on the back wall. The balancing feature intersects and defines part of the outer rim edge.

Abstract: Turbomachines such as air dynamometers are disclosed that include a radial outflow compressor and gas collector. In some examples, the gas collector is designed as a separate component that is coupled to the machine, such as coupled to a frame. In some examples, the collector and frame are intentionally spaced and coupled at discrete points to minimize the transfer of mechanical and thermal energy therebetween. Aspects of the present disclosure also include turbomachines that include at least one impeller bypass flow path for the direct transfer of air between ambient and a location in the collector downstream of the impeller blades. In some examples, such flowpath(s) may allow for the inflow of external ambient air into the collector.

Abstract: A retention assembly for interconnecting first and second rotating components in a gas turbine engine. The second component includes an engagement portion defining protrusions circumferentially spaced apart and extending axially therefrom. A threaded fastener axially retains the second rotating component to the first and has key-receiving slots and a circumferentially-extending groove. A key washer is mounted to the fastener and defines first and second axial surfaces. The key washer has a first set of keys extending radially inwardly from a radially inner surface and received within the key-receiving slots and a second set of keys extending from the second axial surface. A retaining ring is disposed within the groove, is radially retained by the protrusions extending axially from the second component, axially retained between the second set of keys and the second axial surface, and radially spaced apart from the second set of keys to define a radial gap therebetween.

Abstract: A rotor includes: a hub; and a plurality of blades disposed on the hub. Each of the plurality of blades has a suction surface, a pressure surface, a leading edge, a trailing edge, a tip-side edge, and a hub-side edge. The suction surface has a first curved surface portion curved convexly toward the trailing edge such that the trailing edge is inclined to a pressure surface side in a first region which is a partial region, in a blade height direction of the blade, of a region connected to the trailing edge.

Abstract: A vacuum pump includes a rotor that has a rotor central portion and a plurality of stages of rotor blade portions extending from the rotor central portion and having a predetermined elevation angle, and a casing that houses the rotor therein. The rotor further includes a rotor fin. The rotor fin includes a fin shaft portion connected to an end of the rotor central portion, and a transfer blade that extends from the fin shaft portion and causes particles to bounce back in a direction toward an outer periphery of the rotor, the particles falling onto the abovementioned end through an inlet port. The height of the transfer blade and the number of transfer blades are set based on the fall velocity of the particles and the rotation speed of the rotor, such that the particles are prevented from falling onto the abovementioned end without colliding with the transfer blade.

Abstract: A turbine for a turbo-machine is proposed in which, at a gas inlet for a turbine wheel, vanes extend from a nozzle ring though slots in a shroud. The nozzle ring and shroud are relatively rotatable about a rotational axis of the turbine by at least 0.1 degrees. In use, the nozzle ring and shroud are relatively rotated to bring one side of the vane into close contact with one surface of the slot, to inhibit leakage of gas between the vane and the slot surface. For this purpose the respective surfaces of the nozzle and slot can be configured to closely conform to each other. If there is differential thermal expansion of the shroud and nozzle ring, the nozzle ring and shroud can relatively rotate, to withdraw the vane from the edge of the slot to relieve the pressure between them.

Abstract: A turbine rotor blade according to at least one embodiment to be connected to a rotational shaft so as to be rotatable around an axis includes a hub having a hub surface inclined with respect to the axis in a cross-section along the axis; and a plurality of rotor blades disposed on the hub surface. In a throat portion where a blade-to-blade distance between two adjacent rotor blades is smallest, a value (Lt/r) obtained by dividing the blade-to-blade Lt at a given radial position by a distance r from the axis to the radial position is maximum at a position where a dimensionless span length is in a range of 0.2 to 0.65, assuming that the dimensionless span length is 0 at a position of a root end portion on a hub side and is 1 at a position of a tip end portion opposite to the hub side.

Abstract: Provided is an aerodynamic structure for mounting to a surface of a wind turbine rotor blade, which aerodynamic structure includes a plurality of rectangular comb elements and/or a plurality of angular comb elements, wherein a comb element includes comb teeth arranged in a comb plane that subtends an angle to the surface of the rotor blade. The embodiments further describe a wind turbine rotor blade including such an aerodynamic structure.

Abstract: A cooled turbine component in a turbine engine is provided. The cooled turbine component includes a brazed in heat transfer feature, the brazed in heat transfer feature including a thin film including a heat transfer feature incorporated into a surface of the film. The thin film is capable of conforming to a surface of the cooled turbine component and is attached to the surface of the cooled turbine component via a braze material. A method for cooling a turbine component in a turbine engine is also provided.