Abstract: A turbomachine having a contrarotating turbine for an aircraft, the turbomachine including a contrarotating turbine of which a first rotor is configured to rotate in a first direction of rotation and is connected to a first turbine shaft, and a second rotor configured to rotate in an opposite direction of rotation and connected to a second turbine shaft. The first rotor includes turbine wheels interleaved between turbine wheels of the second rotor, the turbomachine further including a planetary-type epicyclic mechanical reduction gear which has a sun gear driven in rotation by the second shaft, a ring gear driven in rotation by the first shaft, and a planet carrier attached to a first stator casing of the turbomachine located upstream of the contrarotating turbine with respect to a direction of flow of gas in the turbomachine. The turbomachine includes bearings for guiding the first and second shafts.

Abstract: A turbomachine with a counter-rotating turbine for an aircraft includes a counter-rotating turbine and a mechanical reduction gear with an epicyclic, planetary-type gear train. The gear train includes a planet carrier secured to a stator housing of the turbomachine situated upstream from the counter-rotating turbine in relation to a direction of gas flow within the turbomachine. The planet carrier is secured to the stator housing by an annular part with an elongated shape extending inside the second shaft. The annular part includes an upstream end secured to the intermediate casing and a downstream end coupled to the planet carrier. The annular part also includes an integrated circuit for conveying lubrication oil from its upstream end to the planet carrier.

Abstract: Turbomachine (10) having a contrarotating turbine for aircraft, the turbomachine comprising a contrarotating turbine (22) of which a first rotor (22a) is configured to rotate in a first direction of rotation and is connected to a first turbine shaft (36), and a second rotor (22b) is configured to rotate in an opposite direction of rotation and is connected to a second turbine shaft (38), the first rotor comprising turbine discs that are interleaved between turbine discs of the second rotor, said first shaft (36) being guided by at least two guide bearings (60, 62) mounted between this first shaft and a stator casing, and said second shaft (38) being guided by at least two guide bearings (56, 58) mounted between this second shaft and another stator casing (28).

Abstract: A turbomachine with a counter-rotating turbine for an aircraft includes a counter-rotating turbine and a mechanical reduction gear with an epicyclic, planetary-type gear train. The gear train includes a planet carrier secured to a stator housing of the turbomachine situated upstream from the counter-rotating turbine in relation to a direction of gas flow within the turbomachine. The planet carrier is secured to the stator housing by an annular part with an elongated shape extending inside the second shaft. The annular part includes an upstream end secured to the intermediate casing and a downstream end coupled to the planet carrier. The annular part also includes an integrated circuit for conveying lubrication oil from its upstream end to the planet carrier.

Abstract: The invention concerns a power transmission system of a turbomachine, comprising: a speed reducer (12) comprising a sun gear (15) rotationally secured to a power shaft (5) with a longitudinal axis, an outer ring gear (18) rotating a rotor shaft along the longitudinal axis, and a planet carrier (17), and a device (40) for recovering oil ejected by centrifugal effect and comprising an annular gutter (41) for recovering the ejected oil, the gutter being attached to a fixed annular housing (26) and having a recovery chamber (42) and a first wall portion (43) disposed at least partially facing oil ejection means (30) of the speed reducer for directing the oil to the recovery chamber. According to the invention, the recovery chamber is provided with an inlet opening (45) directed radially outwardly and defined in a plane radially lower than a plane where an outlet port (33) of the ejection means is defined.

Abstract: The invention concerns a power transmission system of a turbomachine, comprising: a speed reducer (12) comprising a sun gear (15) rotationally secured to a power shaft (5) with a longitudinal axis, an outer ring gear (18) rotating a rotor shaft along the longitudinal axis, and a planet carrier (17), and a device (40) for recovering oil ejected by centrifugal effect and comprising an annular gutter (41) for recovering the ejected oil, the gutter being attached to a fixed annular housing (26) and having a recovery chamber (42) and a first wall portion (43) disposed at least partially facing oil ejection means (30) of the speed reducer for directing the oil to the recovery chamber. According to the invention, the recovery chamber is provided with an inlet opening (45) directed radially outwardly and defined in a plane radially lower than a plane where an outlet port (33) of the ejection means is defined.

Abstract: The present invention relates to a method for dimensioning a turbomachine comprising a casing and a disc to which at least one blade is secured, said disc being rotationally driven by a shaft about a turbomachine axis (z), comprising: —acquisition (E1) of the coordinates (P) of the ends of the leading edge and of the trailing edge of the blade in a frame of reference connected with the disc; —expression (E2) of the coordinates (P?) of the ends of the leading edge and of the trailing edge of the blade in a frame of reference connected with the casing; —calculation (E3) of the distance (g) between the casing and the ends of the leading edge and trailing edge of the blade from the coordinates (P?) expressed in the frame of reference connected with the casing; —calculation (E4) of the contact pressures between the blade and the casing along the end of the blade from the calculated distance (g); —calculation (E5) of the reaction forces and moments resulting from contact between the blade and the casing from the ca

Abstract: The present invention relates to a method for dimensioning a turbomachine comprising a casing and a disc to which at least one blade is secured, said disc being rotationally driven by a shaft about a turbomachine axis (z), comprising:—acquisition (E1) of the coordinates (P) of the ends of the leading edge and of the trailing edge of the blade in a frame of reference connected with the disc;—expression (E2) of the coordinates (P?) of the ends of the leading edge and of the trailing edge of the blade in a frame of reference connected with the casing;—calculation (E3) of the distance (g) between the casing and the ends of the leading edge and trailing edge of the blade from the coordinates (P?) expressed in the frame of reference connected with the casing;—calculation (E4) of the contact pressures between the blade and the casing along the end of the blade from the calculated distance (g);—calculation (E5) of the reaction forces and moments resulting from contact between the blade and the casing from the calcula