The present disclosure is directed to a gas turbine engine defining a longitudinal direction, a radial direction extended from an axial centerline, and a circumferential direction. The gas turbine engine includes a compressor section, a combustion section, and a turbine section in serial flow arrangement along the longitudinal direction. The gas turbine engine includes a low speed turbine rotor including a hub extended along the longitudinal direction and radially within the combustion section; a high speed turbine rotor including a high pressure (HP) shaft coupling the high speed turbine rotor to a HP compressor in the compressor section; and a first turbine bearing disposed radially between the hub of the low speed turbine rotor and the HP shaft. The HP shaft extends along the longitudinal direction and radially within the hub of the low speed turbine rotor. The high speed turbine rotor defines a turbine cooling conduit extended within the high speed turbine rotor. The first turbine bearing defines an outer air bearing along an outer diameter of the first turbine bearing and adjacent to the hub of the low speed turbine rotor. The first turbine bearing defines an inner air bearing along an inner diameter of the first turbine bearing and adjacent to the HP shaft. The first turbine bearing further defines a cooling orifice adjacent along the longitudinal direction to the turbine cooling conduit of the high speed turbine rotor. The cooling orifice and the turbine cooling conduit are in fluid communication.

The air bearing includes a main body part having a bearing surface opposed to a guide face, first and second flow path parts, which are provided in the main body part, for allowing compressed air supplied from outside to flow, an air supply hole, which is provided in the flow path part, for supplying compressed air to the guide face to form an air film between the bearing surface and the guide face, and a negative pressure generating part, which is provided in the second flow path part intersecting with the first flow path part, for generating a negative pressure for sucking air between the guide face and the main body part by increasing the flow velocity of the compressed air.

Embodiments of a gas bearing for aircraft engines are provided herein. In some embodiments, a gas bearing may include a first shaft; a second shaft disposed concentrically about the first shaft; and a protrusion extending from at least one of an inner surface of the first shaft or the outer surface of the second shaft to form a gap between the first shaft and the second shaft.

A rheometer has a shaft, which is supported rotatably in a gas bearing. The gas bearing has a first bearing element (rotor) attached to the shaft and a second bearing element (stator) that surrounds the first bearing element (rotor) with a distance between the two, forming a bearing gap. At least sections of the second bearing element (stator) are made from a gas-permeable material, and gas is passed through them in such manner that a gas cushion is formed in the bearing gap, by which the first bearing element (rotor) and the shaft are supported without direct contact between the two. It is provided that the first bearing element (rotor) is also made from a gas-permeable material, at least in the areas that face the second bearing element (stator), and which the gas penetrates and forms a preferably static gaseous layer close to the surface as a result of the dynamic pressure or backpressure of the gas.

A bearing includes a bearing pad for supporting a rotary component and a housing attached to or formed integrally with the bearing pad. The housing includes a flexible column extending towards the bearing pad for providing the bearing pad with an airflow. The column supports the bearing pad from a location inward of an outer periphery of the bearing pad along an axial direction of the bearing. With such a configuration, a resistance of the bearing pad along a radial direction of the bearing is less at the outer periphery than a resistance of the bearing pad along the radial direction proximate the column.

A circumferential seal assembly capable of separating a gas into two separate flow paths before communication between a rotatable runner and a pair of seal rings is presented. The seal assembly includes an annular seal housing, a pair of annular seal rings, a rotatable runner, and a plurality of groove structures. The seal housing is interposed between a pair of compartments. The seal rings are separately disposed within the seal housing and separately disposed around the rotatable runner. The groove structures are disposed along an outer annular surface of the rotatable runner. A gas is communicable onto the groove structures. Each groove structure includes at least two hydrodynamic grooves that separate and communicate the gas onto the seal rings. Each groove includes steps whereby the depth of at least one adjoining step decreases in the direction opposite to rotation with or without the depth of another adjoining steps increasing in the direction opposite to rotation. Each groove is also tapered widthwise.

A circumferential seal assembly capable of separating a gas into two separate flow paths before communication between a rotatable runner and a pair of seal rings is presented. The seal assembly includes an annular seal housing, a pair of annular seal rings, a rotatable runner, and a plurality of groove structures. The seal housing is interposed between a pair of compartments. The seal rings are separately disposed within the seal housing and separately disposed around the rotatable runner. The groove structures are disposed along an outer annular surface of the rotatable runner. A gas is communicable onto the groove structures. Each groove structure includes at least two hydrodynamic grooves that separate and communicate the gas onto the seal rings. Each groove includes steps whereby the depth of at least one adjoining step decreases in the direction opposite to rotation with or without the depth of another adjoining steps increasing in the direction opposite to rotation.

A bearing includes a bearing pad for supporting a rotary component and a housing attached to or formed integrally with the bearing pad. The housing includes a flexible column extending towards the bearing pad for providing the bearing pad with an airflow. The column supports the bearing pad from a location inward of an outer periphery of the bearing pad along an axial direction of the bearing. With such a configuration, a resistance of the bearing pad along a radial direction of the bearing is less at the outer periphery than a resistance of the bearing pad along the radial direction proximate the column.

Certain exemplary embodiments can provide a system, machine, device, manufacture, circuit, composition of matter, and/or user interface adapted for and/or resulting from, and/or a method and/or machine-readable medium comprising machine-implementable instructions for, activities that can comprise and/or relate to, positioning a rotating shaft within a machine via an externally-pressured gas bearing system.

A non-contact bearing is provided. In a suspended state, the non-contact bearing is disposed with a predetermined spacing to a first guide surface. The non-contact bearing includes: a bearing body and a micro electro mechanical layer. The bearing body includes a second guide surface, wherein the second guide surface is opposite to the first guide surface. The micro electro mechanical layer is disposed on the second guide surface, and includes at least one micro sensor and/or at least one micro actuator.