Abstract: Provided is a wind turbine including multiple components generating heat during operation of the wind turbine and a liquid cooling system, wherein the multiple components are thermally coupled by a liquid coolant cycle of the liquid coolant system to an ambient heat exchanger of the liquid coolant system, the ambient heat exchanger being arranged to exchange heat between a liquid coolant contained in the liquid coolant cycle and ambient air, whereby the liquid coolant system includes a heat pump having a cooling operation mode, wherein the heat pump is arranged in the coolant liquid cycle such that the liquid coolant of the liquid coolant cycle is cooled, when the heat pump is operated in the cooling operation mode. Also provided is a method for operating the wind turbine.

Abstract: A dynamic seal for a turbomachine, including a fixed portion provided with at least one abradable wear part and a movable portion including at least one lip arranged to interact with the at least one wear part during the rotation of the movable portion. The wear part includes a structure forming cavities arranged in one or more series such that, in each series, the cavities of this series are superposed radially with respect to the central axis, the structure being configured to limit or prevent the circulation of gas between each pair of radially adjacent cavities. A method for the additive manufacture of the fixed portion of this dynamic seal is also described.

Abstract: A turbine assembly includes a bladed rotor mounted for rotation about an axis of the gas turbine engine, a case assembly, and an internally-cooled tip clearance system. The internally-cooled tip clearance system includes a sensor is configured to monitor a tip clearance formed between the bladed rotor and the case assembly during operation of the gas turbine engine.

Abstract: A liquid cooling head includes an upper casing, an impeller, a bottom casing and a skived fin cooling plate. The upper casing has an inlet and an outlet, the upper casing is fixed on the bottom casing, and the impeller is arranged between the upper casing and the skived fin cooling plate. In addition, the skived fin cooling plate is fixed on the bottom casing, and the impeller sucks the heat-dissipating liquid from the inlet and drives the heat-dissipating liquid passing through the skived fin cooling plate, upwardly passing through the impeller and then discharged from the outlet.

Abstract: A method is for operating a wind turbine. The wind turbine includes a nacelle including a nacelle component, in particular a rotor bearing, and a nacelle air flow influencing unit. The nacelle air flow influencing unit is configured to influence an air flow entering, flowing through and/or exiting the nacelle. The method includes: determining an operating condition of the nacelle component, determining a cooling demand of the nacelle component dependent on the determined operating condition of the nacelle component, controlling an operation of the nacelle air flow influencing unit dependent on the cooling demand of the nacelle component to adapt the air flow to the cooling demand of the nacelle component.

Abstract: Systems and methods for delivering a buffer fluid to a shaft seal of a gas turbine engine are provided. An exemplary system includes, a buffer fluid source, one or more first conduits providing fluid communication between the buffer fluid source and the shaft seal along a first route, and one or more second conduits providing fluid communication between the buffer fluid source and the shaft seal along a second route different from the first route. A heat exchanger is also disposed along the first route to facilitate heat transfer between buffer fluid in the one or more first conduits and a cooling fluid.

Abstract: Systems, methods, and devices for improved cooling of an implantable blood pump employ a thermal conductor to conduct heat to blood flowing through the blood pump. A method includes drawing a flow of blood into a blood pump, passing the flow of blood through the blood pump such that heat flow is conducted to the flow of blood via the thermal conductor, and outputting the flow of blood from the blood pump.

Abstract: A device for pressurizing a turbomachine downstream enclosure, the device being fed by means of a pressurizing air flow and including: a first shaft portion, a second shaft portion coupled to the first shaft portion via internal splines and external splines and extending, at a distance, inside the first shaft portion. The device includes at least a first passage made through the splines, and at least one orifice passing right through the second shaft portion, the orifice being arranged upstream of the first passage, in fluidic communication with the first passage, and opening out inside the second shaft portion so as to allow the pressurizing air flow to circulate from the first passage, between the first and second shaft portions, towards the downstream enclosure.

Abstract: A method for provisionally ensuring the functional capability of a housing of a machine in the event of damage to the housing, the housing having a housing upper part and a housing lower part, which are detachably fastened to each other by housing flanges and by threaded bolts that extend through the housing flanges and are secured by nuts, the damage to the housing being at least one crack in one of the housing parts, which extends toward the other housing part. The housing is reinforced by support plates, which are each fastened to the outside of the housing flanges. A housing is reinforced by support plates of this type.

Abstract: A cold plate is provided and includes: a housing disposed with a chamber; a base combined with the housing to form a working space separated from the chamber but connected with the chamber through an interconnecting structure to allow a working medium to flow within the chamber and the working space; a heat transfer structure disposed on the inner side of the base; and a pump disposed within the working space to drive the working medium in the working space. As such, the cold plate can provide better heat dissipation performance.

Abstract: A vacuum pump comprises: a rotor; a stator; a first heating section configured to heat the stator cylindrical portion to a temperature for reducing product accumulation; an exhaust pipe provided at a housing storing the rotor and the stator to discharge gas discharged by the rotor and the stator to an outside of the housing; a second heating section configured to heat the exhaust pipe to a temperature for reducing product accumulation; and a gas passage container arranged in the housing, having an inlet port into which gas discharged through a gap between the rotor cylindrical portion and the stator cylindrical portion flows and an outlet port from which inflow gas flows to the exhaust pipe, and heated to a temperature for reducing product accumulation. A gas-inflow-side end portion of the exhaust pipe is inserted into the outlet port of the gas passage container through a clearance.

Abstract: In a rotary electric machine housing, a first bearing and a second bearing are provided for supporting a rotating shaft. A lubricating oil is supplied to the first bearing and the second bearing. At least one of the first bearing or the second bearing is sandwiched between the compressed air supplied from one side of the rotating shaft in an axial direction thereof and the compressed air supplied from another side of the rotating shaft in the axial direction.

Abstract: A method for upgrading a gas turbine, the method includes: a) removing all guide vanes of the first guide vane stage; b) replacing the removed guide vanes of the first guide vane stage with new or reconditioned guide vanes, wherein blade platforms of the new or reconditioned guide vanes are provided with cooling air bores which fluidically connect a cooling air supply duct to the annular gap and open into the annular gap, and wherein the cooling air bores are arranged in such a manner that more cooling air bores open into regions of an annular gap that are arranged radially inwards from leading edges of the guide vanes than in other regions of the annular gap.

Abstract: A blood pump (10) includes a pump housing (30) having a pump inlet (16) and a pump outlet (18) spaced apart along a longitudinally extending central pump axis (28). The blood pump (10) also includes a rotating assembly (100) comprising an impeller (104). The blood pump (10) further includes partial arc journal bearings (160, 180) that support the rotating assembly (100) for rotation in the housing (30). The rotating assembly (100) is rotatable relative to the housing (30) to pump blood from the pump inlet (16) to the pump outlet (18).

Abstract: Accelerators, methods of manufacturing accelerators, and gas turbine engines are provided. For example, an accelerator for a gas turbine engine defines a radial direction and an axial direction and comprises an annular outer wall, an annular inner wall, an annular channel defined between the outer and inner walls, and a plurality of vanes disposed within the channel. The channel has an inlet for ingress of a cooling fluid and an outlet for egress of the cooling fluid. Each vane extends from the outer wall to the inner wall adjacent the outlet, which is angled such that an exit angle of the cooling fluid is nonzero with respect to both the radial and axial directions. The accelerator may be manufactured using an additive manufacturing method. The accelerator outlet may be disposed immediately upstream of a first turbine rotor blade stage of a gas turbine engine to direct the cooling fluid thereto.

Abstract: Provided is a cold plate including: a heat absorption space for a working medium to be filled therein; a heat transfer structure disposed on a base within the heat absorption space for transferring thermal energy generated from a heat source that is in contact with the base to the working medium; and a flow guide structure disposed in the heat absorption space for guiding the working medium. The flow guide structure of the cold plate can effectively improve the efficiency of thermal energy absorption of the working medium.

Abstract: A process fluid lubricated pump includes a pump having a pump shaft extending from a drive end to a non-drive end, first and last stage impellers, a drive unit exerting torque on the drive end to rotate the pump shaft, a balance drum connected to the pump shaft between the pump and the drive end, the balance drum defining a drum front side facing the pump and a drum back side, a relief passage between the balance drum and a first stationary part configured to be stationary with respect to a housing, the relief passage extending from the drum front side to the drum back side, the pump shaft radially supported in a non-contacting manner during operation of the pump, and a hydrodynamic radial pump bearing supporting the pump shaft, the radial pump bearing arranged at the non-drive end or at the drive end of the pump shaft.

Abstract: A liquid cooling head includes a chassis, an inlet channel, a thermally-conducting structure, a liquid gathering structure, a drain channel and a pump set. The chassis includes a lower chamber and an upper chamber communicated with the lower chamber through a connection opening. The inlet channel is disposed on one side of the chassis, and communicated with the upper chamber for radiating the heat of the working fluid away. The thermally-conducting structure is disposed in the lower chamber for gathering the working fluid passed through the thermally-conducting structure. The drain channel is disposed on one side of the chassis to be communicated with the lower chamber. The pump set for pushing the working fluid in the lower chamber to discharge the working fluid outwards from the drain channel.

Abstract: A vacuum pump system includes a first vacuum pump and a second vacuum pump connected to an exhaust port of the first vacuum pump. The second vacuum pump has a pump portion and a trap portion. The pump portion has a rotor. The trap portion is configured such that a reaction product generated from gas guided to an internal space from the exhaust port of the first vacuum pump by suction by the pump portion is accumulated thereon.

Abstract: An expander system for recovering waste heat, a waste heat recovery system including such an expander system, a vehicle including such a waste heat recovery system and a method for manufacturing such an expander system. The expander system includes a shaft and a coupling portion including a first sealing unit and a second sealing unit. The shaft is inserted through the coupling portion to an expanding unit. The first sealing unit and the second sealing unit are arranged facing one another along the shaft. The first sealing unit and the second sealing unit are configured to seal the shaft in an axial direction relative to the shaft.

Abstract: A gas turbine module includes a gas turbine that has a gas turbine rotor and a turbine shell; an inlet plenum that is connected to an inlet of the gas turbine; an exhaust plenum that is connected to an exhaust of the gas turbine; an enclosure that covers the gas turbine; and a common base on which the gas turbine, the inlet plenum, the exhaust plenum, and the enclosure are mounted. When moving the gas turbine, the gas turbine module is moved together.

Abstract: A strut may include an outer tube including an outer tube first end, an outer tube second end, and a longitudinal axis extending from the outer tube first end to the outer tube second end. The outer tube may define an interior. The strut also may include an additively manufactured inner tube at least partially within the interior of the outer tube of the strut. The additively manufactured inner tube defines an additively manufactured inner tube first end and an additively manufactured inner tube second end. The additively manufactured inner tube first end is integrally joined to the outer tube proximate to the outer tube first end.

Abstract: Provided is a nacelle for a wind turbine extending along a longitudinal axis and including an outer surface and an heat exchanger on the outer surface, the heat exchanger including a plurality of fluid passages for a fluid to be cooled in the heat exchanger and a plurality of air passages for a cooling air flow in thermal contact with the fluid passages, the air passages extending between an inlet surface and an outlet surface of the heat exchanger. The inlet surface is inclined with respect to the longitudinal axis of an installation angle between 0° and 90°.

Abstract: A cooling apparatus that includes a base plate including two heat exchange units and a cover coupled to the base plate and enclosing the two heat exchange units. A recess is defined in the base plate and between the two heat exchange units. The cover and the base plate define a heat exchange chamber that includes the two heat exchange units. The cover has a first set of openings and a second set of openings, and is coupled to the base plate such that the first set of openings is above a first heat exchange unit and the second set of openings is above a second heat exchange unit. The cooling apparatus further includes a first pumping unit on the cover and over the first set of openings and a second pumping unit on the cover and over the second set of openings.

Abstract: A gas turbine engine and method of starting, the gas turbine engine having a rotor comprising at least a shaft mounted compressor and turbine, with a casing surrounding the rotor. The method comprises an acceleration phase, a bowed-rotor cooling phase, during the acceleration, and a combustion phase. The bowed-rotor cooling phase comprises a time where the rotational speed of the rotor is maintained below a bowed-rotor threshold speed until a non-bowed condition is satisfied, wherein the air forced through the gas turbine engine cools the rotor. The combustion phase occurs after the bowed-rotor cooling phase and upon reaching the combustion speed, wherein fuel is supplied to the gas turbine engine is turned on.

Abstract: An electronic device includes a casing, a motherboard, a battery, a fan, and a heat dissipation module. The motherboard is arranged in the casing, and defines a first space with the casing. The battery is arranged in the casing and defines a second space with the motherboard. The motherboard separates the first space and the second space. The fan is arranged in the casing and has a first airflow outlet and a second airflow outlet independent of the first airflow outlet. The first airflow outlet communicates with the first space and the second space. The heat dissipation module is arranged in the casing and transfers heat from the motherboard to the second airflow outlet.

Abstract: A fan structure having integrated rotor impeller, and methods of producing the same are provided. The fan structure includes a fan housing that encircles a longitudinal axis, and defines an airflow direction from an inlet side to an exit side. The integrated rotor impeller structure is disposed to rotate within the fan housing. The integrated rotor impeller structure includes (a) a cylindrical rotor shell being annular about the longitudinal axis, and having a shell length, and (b) an axis rod coaxial with the longitudinal axis, and having an axis rod length of less than or equal to the shell length. An airflow annulus is created therebetween. A blade is disposed within the airflow annulus to extend radially from the external surface of the axis rod to the inside surface of the the cylindrical rotor shell. One or more magnets are integrated within the integrated rotor impeller structure.

Abstract: A fan module is provided. The fan module includes a housing and an impeller. The housing includes a cover plate. The impeller is disposed in the housing and configured to rotate around an axis. The cover plate has an outer outline away from the axis. A tangent line of an endpoint on the outer outline intersects with the axis to form an angle, and the angle is not a right angle.

Abstract: A turbine generator assembly includes a turbine drivably connected to an electrical generator. The turbine includes a propellant input and a spent propellant exhaust. The spent propellant exhaust is connected to an exhaust flow path. An electrical component is connected to an output of the electrical generator such that the electrical component is powered by the electrical generator. A first heat exchanger including a cooling fluid inlet is connected to the exhaust flow path and a cooled feature is configured to be cooled by fluid received through the cooling fluid inlet. The cooled feature is at least a portion of the electrical component.

Abstract: An axial flow turbine according to an embodiment includes: an outer casing; an inner casing provided inside the outer casing; a discharge pipe that is welded and joined to the outer casing and through which a working fluid discharged from the axial flow turbine flows; a sleeve that is provided inside the outer casing and the discharge pipe and guides the working fluid discharged from the axial flow turbine to the discharge pipe; a tubular member that is provided over an outer periphery of the sleeve inside the outer casing and the discharge pipe and covers an inner periphery side of a joint portion between the outer casing and the discharge pipe; an introduction port that introduces a cooling medium into a space demarcated by the outer casing, the discharge pipe, and the tubular member; and a discharge port that discharges the cooling medium introduced into the space.

Abstract: A fan device includes a casing, a stator unit disposed inside the casing, a rotor unit disposed outside the casing corresponding to the stator unit, and a bearing support detachably connected to the casing. The rotor unit is isolated from the stator unit by the casing and includes a rotation shaft, a bearing, a fan wheel, and a rotor. The bearing support partially shields the rotor unit and supports the rotor unit in a manner that the bearing or the rotation shaft is fixed to the bearing support, so that the fan wheel is driven to rotate with respect to the bearing support as the rotor rotates relative to the stator unit, and the rotor unit and the bearing support can be removed together from the casing when the bearing support is removed from the casing.

Abstract: A turbocharger includes a cooling passage. The cooling passage is arranged along a diffuser surface, which faces a diffuser passage in a compressor housing member. The compressor housing member is constituted by combining a first piece, a second piece, and a third piece, which are produced by die casting or the like. The cooling passage is defined by assembling the first piece and the second piece to each other.

Abstract: A vacuum pump comprises: a stator; a rotor that rotates with respect to the stator; a pump casing in which the stator and the rotor are contained, and a suction port and a through-hole for exhaust are provided; a first exhaust duct fixed to an outer circumference of the pump casing so as to communicate with the through-hole for exhaust; and a second exhaust duct that is inserted into at least the through-hole for exhaust with a gap interposed, an exhaust gas passing inside the second exhaust duct.

Abstract: A rotor of a vacuum pump has a circular member that is driven rotatably, a cylindrical member joined to an outer circumference of the circular member, and a thread groove pump flow path formed between the cylindrical member and a stator member surrounding an outer circumference of the cylindrical member. The cylindrical member is made of a material having at least a feature of lower thermal expansivity or lower creep rate than that of a material of the circular member. A gap of a second region provided between a non-joint portion of the cylindrical member and the stator member is set to be smaller than a gap of a first region provided between a joint portion of the cylindrical member and the stator member.

Abstract: A de-icing device for a splitter nose of a dual-flow turbine engine compressor. The device comprises a splitter nose that has an inner flange and that separates a primary flow and a secondary flow, a shroud arranged on the inside of the annular wall and bearing an annular row of vanes and an abradable seal, a de-icing annular space for circulating a de-icing fluid between the nose and the shroud, a partition annularly dividing the annular space including an outer radial flange attached to the inner flange of the splitter nose using the same bolts that are used to attach the outer shroud. The nose has a radial flange for centering the partition, providing a press fit that optimizes the seal.

Abstract: A blood pump having an axially tubular inlet, a tangential chamber adjoining the axial inlet and having a substantially radial outlet, with an axial guide body connected to the outlet and/or to the tangential chamber, an impeller supported on the guide body and having an inner surface facing the guide body and an outer surface as well as blading arranged on the outer surface. At least one part region of the guide body projects from the tangential chamber into the inlet, wherein at least one section of the stator transmitting a force onto the rotor is arranged in the part region. The impeller is supported by a hydrodynamic radial bearing in the radial direction.

Abstract: Methods, apparatuses, and systems associated with tunable pumped two-phase liquid cooling thermal management are disclosed. In embodiments, a tunable cooling apparatus may include a thermoelectric cooler device, TEC, that has a hot side and a cold side, where the cold side is to cool the coolant in route to an inlet manifold of the cold plate before the coolant enters the inlet manifold, and the hot side may be to warm the coolant in route from an outlet manifold of the cold plate after the coolant flows through the cold plate and exits the outlet manifold and or vice versa. In embodiments, the coolant may be either in a liquid state or in a vapor state. Other embodiments may be described and/or claimed.

Abstract: The invention relates to a cover plate (2) for a screw-type centrifugal wheel pump (1), wherein the cover plate (2) has a front side (2h) and a rear side (2i), and wherein the front side (2h) comprises a surface part (2k) which runs in a preferably frustoconical manner and the profile of which is designed to be matched to the rear side of a screw-type centrifugal wheel (25), wherein the surface part (2k) has, in the center thereof, a central opening (2g), wherein the central opening (2g) runs in the direction of an axis (A), and wherein the cover plate (2) has at least one aperture (2a) which is arranged in the region of the surface part (2k) and spaced apart from the central opening (2g), and wherein the aperture (2a) forms a fluid-conducting connection between the front side (2h) and the rear side (2i) of the cover plate (2).

Abstract: In a turbine exhaust structure and a gas turbine, a turbine casing (26) formed in an annular shape to constitute a combustion gas passage A is provided. An exhaust diffuser (31) formed in an annular shape to constitute a flue gas passage (B) is connected to the turbine casing (26) to constitute a configuration. By providing a pressure loss body (61) in the exhaust diffuser (31), efficient pressure recovery can be carried out, which improves turbine efficiency, thereby enabling improvement of the performance.

Abstract: A blower fan includes a lower plate portion made of a material having a thermal conductivity of 1.0 W/(m·K) or more, and a side wall portion made of a material having a thermal conductivity of 1.0 W/(m·K) or more. An upper plate portion arranged to cover an upper side of the impeller includes an air inlet. The upper plate portion, the side wall portion, and the lower plate portion are arranged to together define an air outlet on the lateral side of the impeller. The blower fan further includes a heat source contact portion with which a heat source is to be in contact, the heat source contact portion being arranged in a surface of the blower fan which faces away from the impeller. The heat source contact portion and the side wall portion are arranged to at least partially overlap with each other in a plan view.

Abstract: A heat dissipation module includes a centrifugal fan and a heat pipe. The centrifugal fan includes an outer housing, a heat dissipation fin array, a retaining wall, an impeller and a rotation-driving device. The outer housing includes an axial air inlet, an axial air outlet and a radial air outlet. The heat dissipation fin array is located at an inner wall of the radial air outlet. The retaining wall is located on a flat wall of the outer housing on which the axial air outlet is located. The retaining wall is in contact with an inner wall of an electronic device to collectively form a circulation channel so as to guide airflows output from the axial air outlet through the flat wall with which the heat dissipation fin array is aligned, and into the axial air inlet. The heat pipe is in contact with the heat dissipation fin array.

Abstract: The present document describes a centrifugal ceiling fan. The fan comprises a casing, a motor and a centrifugal propeller. The casing comprises an upper surface comprising an air inlet and a lower surface comprising an air outlet. In an embodiment, the lower surface has a round bowl-like shape including a plurality of openings defining the air outlet. The propeller comprises a shaft and a plurality of blades provided around the shaft. The blades may be curved to push the air in all directions between a first direction substantially perpendicular to the rotation shaft and a second direction substantially parallel to the rotation shaft in order to evenly ventilate the room. The fan may include a heating element for heating the air as it exits from the fan.

Abstract: An active clearance control system for a gas turbine engine includes a structural member that is configured to be arranged near a blade tip. A plenum includes first and second walls respectively providing first and second cavities. The first wall includes impingement holes. The plenum is arranged over the structural member. A fluid source is fluidly connected to the second cavity to provide an impingement cooling flow from the second cavity through the impingement holes to the first cavity onto the structural member. A method includes the steps of providing a conditioning fluid to an outer cavity of a plenum providing an impingement cooling flow through impingement holes from an inner wall of the plenum to an inner cavity, directing the impingement cooling flow onto a structural member, and conditioning a temperature of the structural member with the impingement cooling flow to control a blade tip clearance.

Abstract: A wind turbine having an air-conditioning system is provided. The air-conditioning system controls the climatization of the interior of the nacelle of the wind turbine. The air conditioning system includes at least one air inlet for ventilating the interior with air intake from outside of the wind turbine. The air-conditioning system also includes a heater for heating the air intake.

Abstract: A heat dissipating device for dissipating heat from a heat radiation element includes a base, a fixing frame, a fan, and a securing arm. The fixing frame is fixedly attached to the base, and the fixing frame has two coaxially aligned receiving holes defined therein. The fan includes two coaxially aligned shafts. The aligned shafts are fittingly received in the respective receiving holes, such that the fan is detachably attached to the fixing frame and rotatable about the aligned shafts. The securing arm is rotatably attached to the base, and the securing arm is configured for holding the fan against the base.

Abstract: A gas turbine engine includes a compressor with rotor blades having roots connected into seats of a compressor drum. The rotor blade roots and/or the compressor drum have longitudinal passages for a cooling fluid, connecting higher pressure areas to lower pressure areas of the gas turbine engine.

Abstract: Provided is a seal air supply system including: a seal air compressor 73 provided separately from an exhaust gas turbine turbocharger 27 to generate compressed air; a seal air supply passage 77 through which the compressed air is supplied to a seal air supply part 79 as seal air of the exhaust gas turbine turbocharger 27; and a surplus air inlet passage 81 bifurcating from the seal air supply passage 77 and guiding surplus air of the seal air to an outlet side of an intake gas compressor 27a of the exhaust gas turbine turbocharger.

Abstract: A system and method to cool the air inside the nacelle and the heat generating components, particularly of an offshore wind turbine is presented. The ambient air first enters an air handling unit near the tower bottom where the airborne water droplets and salt particles are removed. The clean air is then compressed adiabatically, thus increasing the dew point temperature of the water vapor in the air. The high pressure, high temperature air from the compressor is then cooled and dehumidified in a sea water-to-air heater exchanger or an air-to-air heat exchanger. The high pressure air from the heat exchanger then enters the turbine at the tower bottom and flows up to the nacelle where it is allowed to expand adiabatically in a duct. The duct helps direct the resulting cold air over the heat generating components. The cold air can also used to cool these components internally. The warm air ultimately exits the nacelle at the rear top.

Abstract: A system and method for sealing a shaft disposed for rotation within a casing, where two axially-spaced seal rings of an oil film seal extend around the shaft and define a clearance therebetween. Oil is pumped into the clearance from an oil reservoir and a portion of the oil is received in an annular port defined in the casing between an outer labyrinth seal and one of the axially-spaced seal rings. The oil mixes with a process gas to for an oil and gas mixture. A blower is in fluid communication with the annular port and circulates the oil and gas mixture to a trap where the oil is separated from the process gas and a separated process gas is returned back to the annular port.

Abstract: One or more heat exchangers mounted in a duct have heat transfer cooling passages therein and a variable geometry flow restrictor is integral with each of the heat exchangers. An annular slide valve axially translatable within the duct is operable to open and close or vary a variable area between the heat exchangers and one of inner and outer casings bounding the duct. The heat exchangers may be being circumferentially distributed around an annular duct and include radial or circumferentially curved heat transfer tubes or vanes.