Abstract: There is disclosed a gas turbine engine including a bearing housing having at least two bearings axially spaced from one another relative to a central axis. The bearing housing has a case between the at least two bearings having a joint configured for relative axial movement between the bearing supports. A method of operating a bearing assembly including the bearing housing is also disclosed.

Abstract: There is disclosed a bearing assembly for a gas turbine engine. The bearing assembly has a central axis and includes at least two bearings being axially spaced from one another relative to the central axis and configured to rotatably support a rotating component of the gas turbine engine. A bearing housing includes bearing supports supporting the at least two bearings. The bearing housing is securable to a casing of the gas turbine engine via hairpin structures being axially spaced from one another.

Abstract: There is disclosed a bearing assembly for a gas turbine engine including at least two bearings axially spaced from one another relative to a central axis, and a squirrel cage secured to a casing of the gas turbine engine. The squirrel cage supports respective bearing loads of the at least two bearings. The squirrel cage has a frangible section between the bearings configured to preferentially fail upon application of a load greater than a preselected threshold bearing load.

Abstract: A journal bearing for a gas turbine engine is described. The journal extends along a central axis from a first axial end face to a second axial end face thereof, and has at least one undercut defined circumferentially about the central axis in one of the first and second axial end faces. The undercut extends toward the other one of the first and second axial end faces of the journal. A stiffening member extends across the undercut to interconnect opposite surfaces thereof. Also described, a journal bearing comprising a tubular body extending axially along a central axis, where the tubular body has a first and a second opposite axial end faces with holes projecting into the first axial end face toward the second axial end face and having a finite depth. The holes are circumferentially disposed about the central axis, and respective webs of material are defined between adjacent holes. A method of operating a journal bearing is also provided.

Abstract: A turbine containment arrangement includes a turbine rotor rotatable about a turbine axis and a casing. The casing extends radially outward of the turbine rotor and includes an outer ring, an inner ring, and a plurality of fins. The inner ring is disposed radially inward from and co-axially with the outer ring and the turbine axis. The outer ring and the inner ring form an annular gap extending therebetween. The plurality of fins is disposed between the outer ring and the inner ring and extends at least partially circumferentially and radially therebetween. The plurality of fins is monolithically formed with the inner and outer rings.

Abstract: A split case compressor including a first compressor case segment including a first split flange extending axially and a first axial flange extending circumferentially about the first compressor case segment. The compressor also includes a second compressor case segment including a second split flange extending axially and a second axial flange extending circumferentially about the second compressor case segment, the first and second split flanges forming an overall split flange for securing the first compressor case segment and the second compressor case segment to each other. The compressor further includes a notch of at least one of the first axial flange and the second axial flange proximate the overall split flange.

Abstract: A gas turbine engine maintenance stand for a gas turbine engine that comprises modules including an engine core module that houses a high pressure compressor and a turbine module that houses a low pressure turbine. The gas turbine engine maintenance stand has a pair of base beams, each base beam having a first end, a midsection and a second end. The stand has an engine core module support that straddles the pair of base beams at their midsection, the engine core module support having engine core module support arms that are configured to engage opposing sides of the engine core module of the gas turbine engine. The stand also has a turbine module support that straddles the pair of beams adjacent their second ends, the turbine module support having turbine module support arms that are configured to engage opposing sides of the turbine module of the gas turbine engine.

Abstract: An assembly for removing particles from a fluid stream includes a first particle remover having a main flow outlet emitting a first reduced-particle stream and a scavenge flow outlet emitting a particle-laden stream, as well as a second particle remover fluidly coupled to the scavenge flow outlet and emitting a second reduced-particle stream.

Abstract: A method and apparatus for generating electricity and producing carbon and heat via biomass fixed bed gasification, said method and apparatus utilising medium calorific value combustible gas to satisfy high-temperature high-pressure boiler heat requirements, and increasing overall electricity generation efficiency. The method and apparatus have low nitrogen oxides amounts, satisfy environmental protection requirements, and do not require denitrification treatment. The method comprises the following steps: feeding a biomass raw material into a gasification apparatus to prepare a medium calorific value biomass combustible gas, and performing gasification on the biomass raw material at 700-850° C. under the effect of an air/water vapour pre-mixed gasification agent to produce a combustible gas, the calorific value of the combustible gas being 1600-1800 kcal, the temperature being 200-300° C.

Abstract: A power plant comprises a boiler, a turbine, a condenser, a feed water heater, a deaerator, a deaerator water level control valve, an extraction system which introduces the steam extracted from the turbine into the feed water heater, an extraction valve, an auxiliary steam introduction system which introduces auxiliary steam into the feed water heater, an auxiliary steam control valve and a control device. When a rapid load increase request is made, the control device controls, to orient the extraction valve in a closing direction, to maintain an opening of the deaerator water level control valve, and to orient the auxiliary steam control valve in an opening direction.

Abstract: A heat recovery system that includes at least one an engine, a radiator, an Organic Rankine Cycle (ORC) and a thermo-electric generator (TEG). The radiator may be coupled to the reciprocating engine, and the ORC may be coupled to the reciprocating engine and to the TEG. A control module in the system is configured to divert reciprocating engine jacket water fluid through any of the radiator, ORC and TEG to increase the energy efficiency of the reciprocating engine through heat recovery caused by the diverted fluid.

Abstract: A rocker arm for a valve train assembly includes: a first body; a second body mounted for pivotal movement with respect to the first body; and a latching arrangement. The latching arrangement includes a latch pin drivable in response to an external actuator from a first position in which the first body and the second body are un-latched to a second position in which the latch pin latches the first body and the second body together. The latching arrangement includes a piston member and a first biasing member. The piston member is arranged such that if the external actuator attempts to cause the latch pin to be driven from the first position to the second position at a time when the latch pin is prevented from being driven, the piston member moves to bias the biasing member so that the biasing member urges the latch pin to the second position.

Abstract: An adjusting device having at least one tappet assembly. The at least one tappet assembly comprises a tappet, at least one guide cylinder, and a pole core. The tappet is arranged in the guide cylinder in a movable manner along a longitudinal axis, and a non-magnetic connection socket is arranged between the guide cylinder and the pole core. The guide cylinder and the pole core are arranged at a distance to each other in the longitudinal axis by means of the connection socket.

Abstract: A camshaft phaser includes a stator defining a cavity and configured to receive power from an engine crankshaft. The phaser further includes a rotor supported within the cavity and rotatable relative to the stator. The rotor has a first face, a second face, and a first hole extending from the first face to the second face. A target wheel of the phaser has a plate portion configured to be read by a camshaft-position sensor and a hub portion seated on the first face. The hub portion defines a second hole that is aligned with the first hole. A pin extends through the first and second holes to rotationally align and secure the target wheel to the rotor.

Abstract: A device for adjusting camshaft phase is proviced that includes a stator, a rotor and two guard caps that limit the rotor are fixedly provided at axial ends of the stator. The device further includes a belt pulley that is sleeved on the periphery of the stator and the guard caps and fixedly connected to the stator or the guard caps. An annular seal is disposed on the device and includes a first sealing portion and a second sealing portion located at axial ends. The seal body is fixedly provided between the stator, the guard caps and the belt pulley, and the annular seal encloses a sealed cavity. The stator, the rotor and the guard caps are fixedly provided in the sealed cavity.

Abstract: The present disclosure describes a valve train for an internal combustion engine. The valve train includes a camshaft with a first cam and a second cam, a rocker lever assembly with a shifting pin that is adjustable in an axial direction between at least two positions, a cam follower mounted on the shifting pin, an adjusting device for adjusting a control pin arranged in the shifting pin, and a guide contour arranged on the camshaft having a first guide track and a second guide track intersecting the first guide track in an X-like manner. The control pin engages into the guide tracks and adjusts the shifting pin to adjust the cam follower. The adjusting device includes a control rod that is shiftable parallel to the shifting pin and contacts the control rod.

Abstract: Poppet valve for an internal combustion engine including a valve stem and a single circular valve head attached at one end of the valve stem. The valve head has a circular peripheral contour and an arcuate edge without any sharp elements to avoid turbulence and improve flow around the valve to therefore maximize flow velocity. This translates into increased cylinder breathing in the intake cycle and reducing back pressure in the exhaust cycle.

Abstract: In an electric oil pump, a motor includes a main body including a coil, bus bars electrically connected to lead wires of the coil, and a shaft including a portion on one side in an axial direction protruding from an end of the main body on the one side in the axial direction and connected to a pump, a control board includes a power supply input portion and a power supply output portion and is disposed in a posture in which any one of a first surface and a second surface of the control board lies in the axial direction, the power supply input portion is at an end portion of the control board on the other side in the axial direction, and bus bar terminals are disposed on one side of the main body in the axial direction.

Abstract: Various example embodiments relate to rotating coalescers. One embodiment includes a housing comprising a first housing section having a blowby gas inlet structured to receive crankcase blowby gases from a crankcase. The housing further comprises an oil outlet. The rotating coalescer includes an endcap and filter media. The filter media is arranged in a cylindrical shape and is coupled to and positioned between the crankcase blowby gases passing through the filter media by coalescing and separating oils and aerosols contained in the crankcase blowby gases. The rotating coalescer includes a hollow shaft extending through the housing and positioned radially inside of the filter media. The hollow shaft forms a blowby gas outlet structured to route filtered crankcase blowby gases out of the housing. The rotating coalescer further includes a drive mechanism operatively coupled to the hollow shaft.

Abstract: A heat exchanger assembly, in particular an exhaust gas cooler, having a gas inlet pipe attached to an inlet diffuser to improve flow distribution of the gas in a case with a heat exchanger core within. The gas inlet pipe configured to disrupt the momentum of flow of the gas due to at least one bend upstream of the inlet diffuser. The gas inlet pipe including at least two intermediate bends which define multiple section of the gas inlet pipe, at least two of the sections redirecting flow of the gas before an outlet of the gas inlet pipe to more evenly distribute the gas at the outlet of the gas inlet pipe upstream of the inlet diffuser.

Abstract: A particulate filter, including: a pillar-shaped honeycomb structure portion having a plurality of first cells extending from a first end face to a second end face, the first end face being open and the second end face being plugged, and a plurality of second cells extending from the first end face to the second end face, the first end face being plugged and the second end face being open, in which the first cells and the second cells are alternately arranged adjacent to each other with porous partition walls interposed therebetween; and a low thermal conductive layer covering a part or the whole of an outer peripheral side surface of the pillar-shaped honeycomb structure portion, the thermal conductivity in a thickness direction of the low thermal conductive layer being 0.6 W/(m·K) or less.

Abstract: A method for regenerating an exhaust gas filter on which soot is deposited, including sequentially conducting: a step 1 of impregnating the filter with a liquid having 50% by mass or more of a component having a boiling point of 550° C. or less when an ambient temperature in the filter is at least 40 ° C. lower than the boiling point; a step 2 of raising the ambient temperature in the filter after the impregnation to a temperature equal to or higher than the boiling point of the component; and a step 3 of supplying an oxygen-containing gas at a temperature exceeding 550° C. to the filter to burn the soot.

Abstract: An exhaust system for an internal combustion engine, and methods of using, the system comprising a hydrocarbon trap; and a gasoline particulate filter, located downstream from the hydrocarbon trap.

Abstract: A hybrid vehicle includes: an internal combustion engine; a rotating electric machine; a planetary gear mechanism to which the internal combustion engine, the rotating electric machine and an output shaft are connected; a catalyst that purifies exhaust gas of the internal combustion engine; and a controller that controls the internal combustion engine and the rotating electric machine. The controller controls the internal combustion engine and the rotating electric machine to perform catalyst temperature control to shift an operating point on a map representing a relationship between rotation speed of the internal combustion engine and torque generated by the internal combustion engine so that the catalyst has a temperature within an appropriate temperature range. Degradation of the catalyst can be suppressed without deteriorating the function of the catalyst.

Abstract: An apparatus is provided for the catalytic treatment of exhaust gas from an internal combustion engine comprising: a. a casing having an exhaust gas inlet and a treated exhaust gas outlet; b. a heater disposed within the casing, through which exhaust gas may flow; and c. a catalyst article disposed within the casing adjacent to the heater, through which exhaust gas can flow; wherein the heater comprises an electrically resistive wire mounted on an electrically insulating frame.

Abstract: An exhaust gas treatment system (1) comprises a catalyst article (5) for the treatment of an exhaust gas, the catalyst article (5) comprising a non-metallic substrate (20) comprising a plurality of catalytically-active transition-metal-doped iron oxide magnetic particles (45), and an inductive heater (70) for inductively heating the plurality of catalytically-active magnetic particles by applying an alternating magnetic field.

Abstract: A mixer device for an exhaust gas aftertreatment system of a motor vehicle includes a cylindrical housing that has a lateral wall in which there is an injection opening for an exhaust gas aftertreatment medium, a first end wall in which at least one inlet opening is formed, and a second end wall in which an outlet opening is formed; at least one air guiding element situated in the housing, that extends in curved a manner, and that guides an exhaust gas flow from the at least one inlet opening to the outlet opening; and at least one impact surface for the exhaust gas flow and/or the exhaust gas aftertreatment medium situated in the housing downstream from the inlet opening and oriented essentially perpendicularly to the injection direction of the exhaust gas aftertreatment medium.

Abstract: An exhaust gas purification device including: a first case communicating with an exhaust manifold of an engine and internally including a first exhaust gas purification body for removing a carbon compound; and a second case communicating with an exhaust outlet of the first case and internally including second exhaust gas purification bodies for removing a nitrogen compound. The first case and the second case are arranged above the engine and in an L-shape to respectively extend along two side surfaces of the engine, the two side surfaces being adjacent to each other.

Abstract: A modular system for exhaust heat recovery devices has heat exchangers which differ by different external dimensions, in particular different cross-sections, and identically configured exhaust gas carrying housings into each of which one of the heat exchangers can be introduced. Various tubular adapters are adapted to the external dimensions of the heat exchangers and are used to fasten the associated heat exchanger at its connection ends to the exhaust gas carrying housing. Furthermore, a tubular adapter for a corresponding modular system and a vehicle which has a corresponding exhaust heat recovery device are provided.

Abstract: Systems and apparatus to generate electrical power from aircraft engine heat are described herein. An example aircraft engine described herein includes a gas turbine engine having an engine housing. The engine housing defines a flow path through a combustion chamber and a core exhaust cavity. The example aircraft engine also includes an energy-generating cell coupled to a portion of the engine housing defining the core exhaust cavity. The energy-generating cell is to generate electrical energy from high temperature fluid in the core exhaust cavity.

Abstract: A method for estimating a volume of thawed liquid in a motor vehicle tank, wherein the following operations are executed at regular time intervals: obtaining a temperature of the ambient air outside the tank using a thermometer; determining, according to said temperature outside the tank and by a first pre-established relation, a thermal energy transfer between the contents of the tank and the outside environment; determining, as a function of the power produced by a heating element, and by a second pre-established relation, a thermal energy transfer between the heating element and the contents of the tank; determining, as a function of the energy transfers, and by a third pre-established relation, an amount of thawed or refrozen liquid, during said time interval; the amounts of thawed and refrozen liquid are added during the preceding consecutive time intervals to estimate a volume of thawed liquid present in the tank.

Abstract: An exhaust pipe structure includes a front bank exhaust pipe connected to an exhaust manifold on a front bank of the V engine; an intermediate exhaust pipe connected to a downstream side of the front bank exhaust pipe; and a rear exhaust pipe connected to a downstream side of the intermediate exhaust pipe, wherein the front bank exhaust pipe and the intermediate exhaust pipe are connected with each other via a ball joint, the intermediate exhaust pipe and the rear exhaust pipe are connected with each other via a ball joint, and a flexible pipe is attached to the front bank exhaust pipe.

Abstract: A connector system for attaching diffusers to automotive vehicle exhaust systems which, in accordance with the characteristics thereof, provides a connector system in a specific structure of the mechanical type and based in an outlet nozzle with a groove flange, a tongue flange making the interface outlet nozzle-diffuser, an outlet connector with a tongue flange making the interface to the automotive vehicle exhaust system, a groove flange making the interface outlet connector-diffuser, and fixing clamps for the pairs of tongue-groove flanges, in order to provide complete optimization procedures to press fit and fasten the diffusers and their parts such as outlet nozzles and outlet connectors to automotive sports vehicle exhaust systems, coupled with a 360-degree double rotating system of their parts.

Abstract: A cooling device for a power source for a boat propulsion apparatus includes a cooling water passage. The cooling water passage includes a passage provided in the power source, in which an engine or an electric motor is used as the power source of the boat propulsion apparatus that propels a boat. Water from outside the boat is taken into the cooling water passage as cooling water to cool the power source, and the cooling water after cooling the power source is drained from the cooling water passage. From the cooling water flowing through the cooling water passage, foreign substances having a size that clogs the cooling water passage are removed. The cooling water passage is provided with a filter device which can filter residual foreign substances remaining in the cooling water.

Abstract: An active air flap includes: a first air flap disposed between a ventilation opening of a bumper and a radiator, and openably disposed in a first section facing the radiator; a second air flap disposed between the ventilation opening of the bumper and the radiator, and openably disposed in a second section bordering the first section facing the radiator; and an air guide configured to guide air introduced into the radiator toward the first air flap and the second air flap.

Abstract: A cooling system configured to cool a combustion engine (2) and at least one further object (18) in a vehicle (1) includes a main radiator (8), a main radiator bypass line (9) directing coolant past the main radiator (8), a first valve device (6) receiving coolant from a coolant line (5) and directing it to the main radiator line (7) and the main radiator bypass line (9), an auxiliary circuit (14) directing coolant to the further object (13, 28), a main radiator outlet line (7b) directing at least a part of the coolant leaving the main radiator (8) to the auxiliary circuit (14), and a second valve device (20) receiving coolant from the main radiator (11) and/or the main radiator bypass line (9) and directing it to the auxiliary circuit (14) and/or the engine inlet line (3).

Abstract: The invention relates to the technical field of heat dissipation, in particular to a piston-based pressure reduction structure used for a water-cooling radiator, and a water-cooling radiator. By adoption of the piston-based pressure reduction structure used for a water-cooling radiator, and the water-cooling radiator, the problem of liquid leakage caused by an excessively high pressure in existing water-cooling radiators is solved.

Abstract: An engine system capable of controlling an intake air flow includes a combustion chamber, an ignition plug, an intake air flow control valve, and a controller. The controller performs, in at least a part of an operating range, SPCCI combustion in which after jump-spark ignition combustion of a portion of a mixture gas inside the combustion chamber by a jump-spark ignition of the ignition plug, compression ignition combustion of the remaining mixture gas is carried out by a self-ignition. The controller strengthens, at least in a part of the operating range of SPCCI combustion, the intake air flow inside the combustion chamber by controlling the intake air flow control valve. The controller controls, in a middle-load range of the operating range where SPCCI combustion is performed, the intake air flow control valve so that the intake air flow becomes weaker than in a high-load range and a low-load range.

Abstract: An in-cylinder injection engine includes: a cylinder head that includes a gasket surface stacked on a seating face of a cylinder block and defines a combustion chamber between a piston and a ceiling surface gradually receding from an imaginary plane including the gasket surface in going toward a center of the cylinder head; two intake ports disposed side by side and opened in the ceiling surface of the cylinder head; and a fuel injection valve mounted to the cylinder head and having an injection port facing the combustion chamber at a position between an opening of the intake port and the gasket surface. The intake port is formed to have a shape of introducing an airflow laterally into the combustion chamber along the imaginary plane. Accordingly, the in-cylinder injection engine can reduce attachment of injected fuel to a wall surface of a cylinder bore.

Abstract: A turbocharger includes a first scroll member made of sheet metal, extending in a circumferential direction of an impeller shaft, having an opening that is opened to the bearing housing, and forming a part of a wall surface of the first turbine scroll passage, a second scroll member made of sheet metal, extending in the circumferential direction of the impeller shaft, having an opening that is opened to the bearing housing, and forming a part of a wall surface of the second turbine scroll passage, and a closing member closing the opening of the first scroll member and forming the wall surface of the first turbine scroll passage on the side thereof adjacent to the bearing housing, and closing the opening of the second scroll member and forming the wall surface of the second turbine scroll passage on the side thereof adjacent to the bearing housing.

Abstract: An electronic compressor bypass valve (eCBV) module includes a pedestal housing, and a compressor bypass valve mounted to the pedestal housing. An inlet port, a first outlet port, and a second outlet port are integrally formed as part of the pedestal housing, where pressurized air flows into the inlet port. The eCBV module also includes a venturi device at least partially disposed in the second outlet port. When the compressor bypass valve is in an open position, a portion of the pressurized air flows through the first outlet port, and a portion of the pressurized air flows from the inlet port through the venturi device and through the second outlet port. When the compressor bypass valve is in the closed position the pressurized air is prevented from flowing into the first outlet port, and all of the pressurized air flows through the venturi device and through the second outlet port.

Abstract: The invention relates to a method for operating an internal combustion engine (100) having an exhaust-gas turbocharger (5, 10, 15) for compressing the air fed to the internal combustion engine (100), wherein a drive power of a turbine (10) of the exhaust-gas turbocharger (5, 10, 15) in an exhaust tract (20) of the internal combustion engine (100) is changed through variation of a turbine geometry of the turbine (10), wherein, in a first control algorithm (I), a setpoint charge pressure (pLSoll) at the outlet of the compressor (5) of the

Abstract: An actuator includes an electric motor, an output shaft and an output lever. The output lever is fixed to one end portion of the output shaft, which is located at an outside of a housing. The output lever includes a cylindrical hole, through which a cylindrical portion of the output shaft is received, and a cutout, which is radially outwardly recessed from the cylindrical hole. A part of an inner wall surface of the cutout, which is connected to an inner wall surface of the cylindrical hole, is defined as a root corner. The root corner is shaped in a convex curved surface form in a view taken in an axial direction of the cylindrical hole.

Abstract: There is disclosed a method of operating an engine assembly, including: driving a load with an internal combustion engine and an output of a turbine section, the turbine section driven by combustion gases from an exhaust the internal combustion engine; and injecting fuel upstream of the turbine section and downstream of the exhaust of the internal combustion engine. An engine assembly having a secondary injector for injecting fuel upstream of the turbine section and downstream of the combustion engine is also disclosed.

Abstract: Cogeneration system (200, 300) comprising: a boiler (201, 301) able to heat water for domestic use; a combustor (201a, 301a) placed into the boiler; a compressor (204, 304); a heat exchanger (202, 302) for the exchange of thermal energy between the combustion fumes generated in the combustor (201a, 301a) and a fluid coming from the compressor (204, 304); a gas turbine (203, 303); a current generator (205, 305) and a current converter (206, 306) able to produce electrical energy; a main fumes/water exchanger (207, 307) able to recover thermal energy. The cogeneration system (200, 300) comprises also a by-pass valve (210, 310) configured to adjust the flow of fluid entering the gas turbine (203, 303).

Abstract: A gas turbine engine, in particular for an airplane, includes a bladed rotor, a shaft driven by a turbine and an electrical generator including first and second generator components that can be rotated and magnetically coupled to one another, the first one being fixed to the shaft and the second one being mechanically coupled to the bladed rotor so as to drive the bladed rotor.

Abstract: An acoustic liner may include an acoustic core having an array of resonant cells, and an acoustic screen disposed across the array of resonant cells. The resonant cells include a plurality of cell walls and a resonant space defined by the plurality of cell walls. The acoustic core may include a folded acoustic core. Additionally, or in the alternative, at least some of the resonant cells may include an oblique polyhedral cellular structure and/or a multitude of sound-attenuating protuberances. The acoustic screen may include a reticulate membrane and a support lattice.

Abstract: An air inflow lip of a nacelle for a turbojet of an aircraft, including a cavity defined by a leading edge of the nacelle and by an annular wall, includes an inner wall, an acoustic treatment device, and a pneumatic de-icing device including a de-icing fluid supply device. The inner wall of the air inflow lip includes acoustic boreholes and the pneumatic de-icing device includes a honeycombed de-icing plate mounted inside the cavity on the inner wall of the air inflow lip. Also included are conduits for the circulation of a de-icing fluid and acoustic wells communicating with the acoustic boreholes.

Abstract: The present invention discloses a supersonic inlet with synchronous adjustment of capture area and throat area, wherein the throat area may be adjusted by providing a movable throat section, while the capture area may be adjusted by providing a movable cowl section at the front end of the cowl lip, thereby realizing the effect that the capture area and the throat area of the inlet may be adjusted in synchronization. Meanwhile, the present invention also provides a control method and a design method of the above-mentioned inlet. The present invention greatly simplifies the actuation system and control system, significantly reduces the weight of the accessory system, and enables the performance of the inlet within a wide envelope range to be maintained in an excellent state.

Abstract: The invention relates to a plain bearing device having a primary sliding surface between a first pair of concentrically arranged structural elements, wherein, in a normal operating state, a relative rotational movement between the structural elements along the primary sliding surface is possible, characterized by at least one secondary sliding surface between a second pair of concentrically arranged structural elements, wherein a coupling means, in the normal operating state, prevents a relative rotational movement between the second pair of structural elements, and wherein, if a predeterminable event occurs, the coupling means is automatically releasable, such that a relative rotational movement between the second pair of structural elements along the at least one secondary sliding surface is made possible. The invention furthermore relates to a method for operating a plain bearing device, and to a gas turbine engine.