Abstract: A turbine housing assembly seal can include a cylindrical portion that defines an opening having an axis where the cylindrical portion is disposed at a cylinder radius from the axis; a lower edge disposed at a lower edge radius that exceeds the cylinder radius; an sloped annular portion that extends radially inwardly from the lower edge; a lower bend that extends from the sloped annular portion to a lower axial position of the cylindrical portion; an upper bend that extends from an upper axial position of the cylindrical portion; and an upper edge that extends radially outwardly from the upper bend to an upper edge radius that exceeds the cylinder radius and that is less than the lower edge radius.

Abstract: A variable-nozzle turbocharger includes a variable vane mechanism that has an annular nozzle ring supporting an array of rotatable vanes, an insert having a tubular portion sealingly received into a bore of the turbine housing and having a nozzle portion extending radially out from one end of the tubular portion and being axially spaced from the nozzle ring with the vanes therebetween, and a plurality of two-piece self-centering spacer assemblies connected between the nozzle portion of the insert and the nozzle ring. Each spacer assembly comprises a tubular sleeve and a separate pin that passes through the through-passage of the sleeve, end portions of the pin being secured respectively to the nozzle ring and the nozzle portion. One end of each sleeve has a conical surface and engages in a corresponding conical countersink in the adjacent face of the nozzle ring or nozzle portion.

Abstract: An assembly can include a turbine wheel; a turbine housing that includes a lower turbine housing surface that extends from an exhaust volute to a cylindrical surface that defines an upper portion of a turbine wheel space; a shroud component that includes a contoured surface disposed between an inner end of an upper shroud component surface and an inner end of a lower shroud component surface where the contoured surface defines a lower portion of a turbine wheel space; and a seal mechanism where the turbine housing and the shroud component form an axial gap between a lower axial position of the cylindrical surface and an upper axial position of the contoured surface where the axial gap is axially positioned between an axial position of an inducer portion of the turbine wheel and an axial position of an exducer portion of the turbine wheel.

Abstract: This invention relates to a control method for a pressurized water nuclear reactor, which comprises a core generating thermal power and means of acquiring magnitudes representative of core operating conditions. The method comprises a step to regulate the temperature of the primary coolant, if the temperature of the primary coolant for a given thermal power is outside a predefined set temperature interval (?TREF) depending on the reactor power. The set temperature interval (?TREF) is characterized by variable amplitude (?T) on a thermal power range between N % and 100% nominal power, where N is between 0 and 100 and comprises a zero amplitude at 100% nominal power, a zero amplitude at N % nominal power.

Abstract: A turbine housing assembly seal can include a cylindrical portion that defines an opening having an axis where the cylindrical portion is disposed at a cylinder radius from the axis; a lower edge disposed at a lower edge radius that exceeds the cylinder radius; an sloped annular portion that extends radially inwardly from the lower edge; a lower bend that extends from the sloped annular portion to a lower axial position of the cylindrical portion; an upper bend that extends from an upper axial position of the cylindrical portion; and an upper edge that extends radially outwardly from the upper bend to an upper edge radius that exceeds the cylinder radius and that is less than the lower edge radius.

Abstract: An assembly can include a turbine wheel; a turbine housing that includes a lower turbine housing surface that extends from an exhaust volute to a cylindrical surface that defines an upper portion of a turbine wheel space; a shroud component that includes a contoured surface disposed between an inner end of an upper shroud component surface and an inner end of a lower shroud component surface where the contoured surface defines a lower portion of a turbine wheel space; and a seal mechanism where the turbine housing and the shroud component form an axial gap between a lower axial position of the cylindrical surface and an upper axial position of the contoured surface where the axial gap is axially positioned between an axial position of an inducer portion of the turbine wheel and an axial position of an exducer portion of the turbine wheel.

Abstract: A variable-nozzle turbocharger includes a variable vane mechanism that has an annular nozzle ring supporting an array of rotatable vanes, an insert having a tubular portion sealingly received into a bore of the turbine housing and having a nozzle portion extending radially out from one end of the tubular portion and being axially spaced from the nozzle ring with the vanes therebetween, and a plurality of two-piece self-centering spacer assemblies connected between the nozzle portion of the insert and the nozzle ring. Each spacer assembly comprises a tubular sleeve and a separate pin that passes through the through-passage of the sleeve, end portions of the pin being secured respectively to the nozzle ring and the nozzle portion. One end of each sleeve has a conical surface and engages in a corresponding conical countersink in the adjacent face of the nozzle ring or nozzle portion.

Abstract: A variable-vane assembly for a variable nozzle turbine comprises a nozzle ring supporting a plurality of vanes affixed to vane arms that are engaged in recesses in the inner edge of a unison ring. The unison ring is rotatable about the axis of the nozzle ring so as to pivot the vane arms, thereby pivoting the vanes in unison. A plurality of guide pins for the unison ring are inserted into apertures in the nozzle ring and are rigidly affixed therein such that the guide pins are non-rotatably secured to the nozzle ring with a guide portion of each guide pin projecting axially from the face of the nozzle ring. Each guide portion defines a shoulder radially overlapping the inner edge of the unison ring such that the unison ring is restrained by the guide pins against excessive movement in both radial and axial directions.

Abstract: A variable-nozzle turbocharger includes a turbine housing and a center housing, and a generally annular nozzle ring and an array of vanes rotatably mounted to the nozzle ring such that the vanes can be pivoted about their axes for regulating exhaust gas flow to the turbine wheel. The vanes extend between the nozzle ring and an opposite wall formed by an insert in the turbine housing. A vane sealing member is supported on the insert, and has a portion disposed between distal ends of the vanes and the insert. This portion of the vane sealing member is configured to be contacted by the distal ends of the vanes when the vanes are in the closed position, while a clearance exists between the portion of the vane sealing member and the distal ends of the vanes when the vanes are in the open position.

Abstract: A variable nozzle for a turbocharger includes a plurality of vanes rotatably mounted on a nozzle ring and disposed in a nozzle flow path defined between the nozzle ring and an opposite nozzle wall. Either or both of the faces of the nozzle ring and nozzle wall include(s) grooves extending substantially transverse to a general flow direction of the flow through the nozzle, and there are clearances between the ends of the vanes and the adjacent faces. Leakage flow through the clearance between the end of each vane and the adjacent face having the grooves must proceed across the grooves, and thus a labyrinthine flow passage is presented to the leakage flow. The labyrinthine passage has a greater resistance to flow than would be the case without the grooves. Accordingly, leakage flow is reduced, which is beneficial to turbine efficiency.

Abstract: A variable-nozzle assembly for a turbocharger includes a generally annular nozzle ring and an array of vanes rotatably mounted to the nozzle ring such that the vanes can be pivoted about their axes for regulating exhaust gas flow to the turbine wheel. A unison ring engages vane arms that are affixed to axles of the vanes, such that rotation of the unison ring causes the vanes to pivot between a closed position and an open position. The vanes have proximal ends that are adjacent a face of the nozzle ring. A vane sealing member is supported on the nozzle ring and has a portion disposed between the proximal ends of the vanes and the face of the nozzle ring. The unison ring includes cams that engage cam followers. Rotational movement of the unison ring causes the cam followers to be moved axially and thereby urge the vane sealing member against the proximal ends of the vanes.

Abstract: A variable-nozzle turbocharger includes a turbine housing and a center housing, and a generally annular nozzle ring and an array of vanes rotatably mounted to the nozzle ring such that the vanes can be pivoted about their axes for regulating exhaust gas flow to the turbine wheel. The vanes extend between the nozzle ring and an opposite wall of the nozzle. An axially floating vane sealing ring is disposed in an annular recess formed in the face of the nozzle ring adjacent proximal ends of the vanes. The vane sealing ring is urged by exhaust gas pressure differential toward the proximal ends of the vanes, and the vanes are thus urged toward the opposite nozzle wall so that distal ends of the vanes are close to or abutting the wall, resulting in a reduction or closing of the gaps at the proximal and distal ends of the vanes.

Abstract: A variable-nozzle turbocharger includes a turbine housing and a center housing, and a generally annular nozzle ring and an array of vanes rotatably mounted to the nozzle ring such that the vanes can be pivoted about their axes for regulating exhaust gas flow to the turbine wheel. The vanes extend between the nozzle ring and an opposite wall of the nozzle. An axially floating vane sealing ring is disposed in an annular recess formed in the face of the nozzle ring adjacent proximal ends of the vanes. The vane sealing ring is urged by exhaust gas pressure differential toward the proximal ends of the vanes, and the vanes are thus urged toward the opposite nozzle wall so that distal ends of the vanes are close to or abutting the wall, resulting in a reduction or closing of the gaps at the proximal and distal ends of the vanes.

Abstract: This invention relates to a control method for a pressurised water nuclear reactor, said reactor comprising a core generating thermal power; means of acquiring magnitudes representative of core operating conditions (thermal power, temperature of the primary coolant); said method comprising a step to regulate the temperature of the primary coolant if the temperature of the primary coolant for a given thermal power is outside a predefined set temperature interval (?TREF) depending on the reactor power, said set temperature interval (?TREF) being characterised by a variable amplitude (?T) on a thermal power range between N % and 100% nominal power, where N is between 0 and 100; a zero amplitude at 100% nominal power; a zero amplitude at N % nominal power; said regulation not taking place while the temperature of the primary coolant is inside said temperature interval (?TREF) for a given thermal power.

Abstract: A turbocharger includes a variable-nozzle assembly that includes an insert having a tubular portion received into a stepped bore of a turbine housing and having a nozzle portion extending radially out from one end of the tubular portion, and a generally annular nozzle ring axially spaced from the nozzle portion and an array of vanes rotatably mounted to the nozzle ring. Sealing of the interface between the tubular portion of the insert and the turbine housing is provided by a sealing ring formed as a generally annular body having a U- or V-shaped cross-section oriented such that an open side of the U- or V-shaped cross-section faces in a radial direction. The U- or V-shaped cross-section defines two opposing legs, one of the legs being engaged against an end face of the tubular portion of the insert and the other leg being engaged against an upstream-facing step surface of the turbine housing bore.

Abstract: A variable-vane assembly for a variable nozzle turbine comprises a nozzle ring supporting a plurality of vanes affixed to vane arms that are engaged in recesses in the inner edge of a unison ring. The unison ring is rotatable about the axis of the nozzle ring so as to pivot the vane arms, thereby pivoting the vanes in unison. The unison ring is radially restrained by a combination of radial guide rollers and fixed axial-radial guide pins secured to the nozzle ring, and is axially restrained by one or more axial stops affixed to the nozzle ring.

Abstract: A turbocharger with a variable nozzle includes a pin mounted in the center housing and extending axially therefrom and engaged in a hole in the nozzle ring to orient the nozzle ring rotationally relative to the center housing. A portion of a length of the pin has a substantially greater compliance than the remainder of the length such that the pin has a flexible tip that engages the hole in the nozzle ring. The flexible tip reduces constraint of thermal deformation of the nozzle ring. The pin portion of greater compliance can be a section of the tube that is slit and expanded. The turbocharger can also include a one-piece locator and heat shield having a locating portion abutting the center housing and the nozzle ring for radially locating the nozzle ring relative to the center housing, and having a shield portion shielding the center housing from hot exhaust gas.

Abstract: A variable nozzle device including an annular nozzle passage formed by a gap between two opposing wall members and at least one vane rotatably supported in the nozzle passage. The vane is formed by a strip of sheet metal contoured to have an outer aerodynamic profile, and having a hollow interior with surfaces mimicking the outer profile. The vane is affixed to a shaft having a wind-stream portion forming two contact surfaces that conformingly receive opposing portions of the interior surfaces.

Abstract: A variable-nozzle turbocharger includes a turbine housing and a center housing, and a generally annular nozzle ring and an array of vanes rotatably mounted to the nozzle ring such that the vanes can be pivoted about their axes for regulating exhaust gas flow to the turbine wheel. The vanes extend between the nozzle ring and an opposite wall formed by an insert in the turbine housing. A vane sealing member is supported on the insert, and has a portion disposed between distal ends of the vanes and the insert. This portion of the vane sealing member is configured to be contacted by the distal ends of the vanes when the vanes are in the closed position, while a clearance exists between the portion of the vane sealing member and the distal ends of the vanes when the vanes are in the open position.

Abstract: A variable nozzle for a turbocharger includes a plurality of vanes rotatably mounted on a nozzle ring and disposed in a nozzle flow path defined between the nozzle ring and an opposite nozzle wall. Either or both of the faces of the nozzle ring and nozzle wall include(s) grooves extending substantially transverse to a general flow direction of the flow through the nozzle, and there are clearances between the ends of the vanes and the adjacent faces. Leakage flow through the clearance between the end of each vane and the adjacent face having the grooves must proceed across the grooves, and thus a labyrinthine flow passage is presented to the leakage flow. The labyrinthine passage has a greater resistance to flow than would be the case without the grooves. Accordingly, leakage flow is reduced, which is beneficial to turbine efficiency.