A gas expander includes a scroll casing, an impeller accommodated in the scroll casing and rotationally driven to a first side in a circumferential direction around a central axis by the gas flowing while expanding from an outside to an inside in a radial direction, a diffuser disposed on a first side in an axial direction with respect to the scroll casing and forming a flow path of the gas discharged from the impeller to the first side in the axial direction and swirling to the first side in the circumferential direction, and a vortex preventer provided in the diffuser, in which the vortex preventer includes a profile rectifying blade portion, which is curved or inclined to a second side in the circumferential direction from the first side toward a second side in the axial direction, at least in a portion of the second side in the axial direction.

A method of developing a suggested blend repair to an airfoil includes the steps of: (a) storing history with regard to a particular airfoil in a particular engine; (b) taking information with regard to new damage to the particular airfoil; (c) reaching an initial blend recommendation based upon step (b); (d) assessing whether the initial blend recommendation of step (c) would be appropriate to repair the new damage based upon a consideration of steps (a)-(c); and (e) reporting a final blend recommendation. An airfoil repair recommendation system is also disclosed.

A method of developing a suggested blend repair to an airfoil includes the steps of: (a) storing history with regard to a particular airfoil in a particular engine; (b) taking information with regard to new damage to the particular airfoil; (c) reaching an initial blend recommendation based upon step (b); (d) assessing whether the initial blend recommendation of step (c) would be appropriate to repair the new damage based upon a consideration of steps (a)-(c); and (e) reporting a final blend recommendation. An airfoil repair recommendation system is also disclosed.

A rotating machine includes a hub portion, wherein the hub portion comprises a forward face and an aft face. The rotating machine further includes a cooling channel formed on either the forward face or the aft face and configured to direct cooling air to a location on the rotating machine, wherein the cooling channel extends from a radially inner location along the face to a radially outer location along the face, and wherein the cooling channel is configured as a recess formed into an outer surface of the face.

A rotating machine includes a hub portion, wherein the hub portion comprises a forward face and an aft face. The rotating machine further includes a cooling channel formed on either the forward face or the aft face and configured to direct cooling air to a location on the rotating machine, wherein the cooling channel extends from a radially inner location along the face to a radially outer location along the face, and wherein the cooling channel is configured as a recess formed into an outer surface of the face.

In one aspect, a method for performing in situ repairs of internal components of a gas turbine engine may generally include inserting a repair tool within an interior of the gas turbine engine such that a tip end of the repair tool is positioned within the gas turbine engine and an exterior end is positioned outside the gas turbine engine. The method may also include positioning the tip end of the repair tool adjacent to a defect of an internal component, wherein the defect defines a fillable volume along a portion of the internal component. In addition, the method may include intermixing two or more constituents of a repair agent within the repair tool at a mixing location defined within the gas turbine engine, and expelling the repair agent from the tip end such that the fillable volume is at least partially filled with the repair agent.

In one aspect, a method for performing in situ repairs of internal components of a gas turbine engine may generally include inserting a repair tool within an interior of the gas turbine engine such that a tip end of the repair tool is positioned within the gas turbine engine and an exterior end is positioned outside the gas turbine engine. The method may also include positioning the tip end of the repair tool adjacent to a defect of an internal component, wherein the defect defines a fillable volume along a portion of the internal component. In addition, the method may include intermixing two or more constituents of a repair agent within the repair tool at a mixing location defined within the gas turbine engine, and expelling the repair agent from the tip end such that the fillable volume is at least partially filled with the repair agent.

An modular apparatus for generating electrical power in a borehole penetrating the earth includes a body comprising first and second mechanical connectors at opposing ends and first and second electrical connectors at the opposing ends, the mechanical connectors and the electrical connectors being configured to connect with the same type of corresponding connectors on another modular apparatus when the modular apparatus and the another modular apparatus are stacked together. The modular apparatus further includes: an electrical generator having a rotor and stator in mechanical communication with the first and second mechanical connectors and in electrical communication with the first and second electrical connectors; and a turbine wheel coupled to or integrated with the rotor and comprising one or more turbine blades that are configured to interact with fluid flowing through the borehole causing the turbine wheel to rotate and the rotor to rotate in order to generate the electrical power.

An modular apparatus for generating electrical power in a borehole penetrating the earth includes a body comprising first and second mechanical connectors at opposing ends and first and second electrical connectors at the opposing ends, the mechanical connectors and the electrical connectors being configured to connect with the same type of corresponding connectors on another modular apparatus when the modular apparatus and the another modular apparatus are stacked together. The modular apparatus further includes: an electrical generator having a rotor and stator in mechanical communication with the first and second mechanical connectors and in electrical communication with the first and second electrical connectors; and a turbine wheel coupled to or integrated with the rotor and comprising one or more turbine blades that are configured to interact with fluid flowing through the borehole causing the turbine wheel to rotate and the rotor to rotate in order to generate the electrical power.

A seal assembly for a gas turbine engine according to an example of the present disclosure includes, among other things, a seal arc segment that has a sealing portion and a first interface portion. The first interface portion defines circumferential mate faces. A support includes a mounting portion and a second interface portion. The mounting portion is configured to be fixedly attached to an engine static structure, and the second interface portion is radially inward of the first interface portion. At least one positioning member is dimensioned to abut the first and second interface portions such that the first and second interface portions are spaced apart by a predetermined distance in a radial direction.