Abstract: A turbine ring assembly includes a ring support structure and a plurality of ring sectors, each including a single piece of ceramic matrix composite material. Each ring sector includes a first portion forming an annular base with an inside face defining an inside face of the turbine ring and an outside face from which there extends two tab-forming portions including ends that are engaged in housings in the ring support structure. The ring sectors present a section that is substantially ?-shaped and the ends of the tabs are held without radial clearance by the ring support structure. The tabs can have a free length in meridian section that is not less than three times their mean width.

Abstract: An assembly with a turbine disk for a gas turbine engine and a bearing-supporting journal, the turbine disk having a radial annular fastening flange secured to a radial annular part of the journal by bolts, the bolts passing successively through fastening bores formed in the radial annular fastening flange of the turbine disk and in the radial annular part of the journal, the radial annular part of the journal having air circulation openings, the openings being formed between the fastening bores of the journal.

Abstract: An aircraft turbine casing configured to carry a set of ring sectors that partly delimits a conduit inside which a gas flow passes through the turbine, including a dynamic mechanism adjusting radial position of ring sectors, an upstream radial lug that connects an upstream end of each ring sector to the casing, and a downstream radial lug that connects a downstream end of each ring sector to the casing. The upstream lug is made as a single piece with the casing and is directly connected to the upstream end of each ring sector.

Abstract: A method controlling a clearance between tips of blades of a turbine rotor of a gas turbine aircraft engine and a ring-shaped turbine shroud of a housing surrounding the blades, the method including: controlling flow and/or temperature of air directed toward the housing according to an estimate of the clearance, the estimate of the clearance is determined upon start-up of the aircraft engine, according to a temperature measured by a temperature sensor including a sensitive element positioned in a free space of the aircraft engine.

Abstract: A system and method for controlling clearance between tips of moving blades of an aeroplane gas-turbine engine and a turbine shroud of an outer casing surrounding the blades. The method includes controlling, according to an operating speed of the engine, a valve positioned in an air duct opening at a stage of the compressor of the engine and leading into a control housing positioned around the outer surface of the turbine shroud and supplied with air coming only from the compressor stage. The valve is opened to cool the turbine shroud during a high-speed phase corresponding to takeoff and climb phases of an aeroplane propelled by the engine and during a nominal-speed phase following the high-speed phase and corresponding to a cruise phase of the aeroplane.

Abstract: A turbine ring assembly includes a ring support structure and a plurality of ring sectors, each including a single piece of ceramic matrix composite material. Each ring sector includes a first portion forming an annular base with an inside face defining an inside face of the turbine ring and an outside face from which there extends two tab-forming portions including ends that are engaged in housings in the ring support structure. The ring sectors present a section that is substantially ?-shaped and the ends of the tabs are held without radial clearance by the ring support structure. The tabs can have a free length in meridian section that is not less than three times their mean width.

Abstract: The invention relates to an assembly including a turbine disk (200) for a gas turbine engine and a bearing-supporting journal (100), the turbine disk (200) comprising a radial annular fastening flange (250) secured to a radial annular part (150) of the journal (100) by bolts (200), the bolts (200) passing successively through fastening bores (120, 220) formed in the radial annular fastening flange (250) of the turbine disk (200) and in the radial annular part (150) of the journal (100), which assembly is characterized in that the radial annular part (150) of the journal (100) comprises air circulation openings (110), the openings (110) being formed between the fastening bores (120) of the journal (100).

Abstract: A hollow turbomachine blade including an internal cooling passage, an open cavity situated at the free end of the blade and defined by an end wall and the side wall of at least one rim which extends between the leading edge and the trailing edge of the blade, and at least one cooling channel connecting said internal cooling passage to said open cavity, said cooling channel opening out at the base of the rim and the wall of the rim forming an angle relative to said end wall that is obtuse, being strictly greater than 90°. An indentation may be formed in the wall of the rim at the outlet from said cooling channel. Said blade advantageously does not include a pressure rim.

Abstract: A hollow turbomachine blade including an internal cooling passage, an open cavity situated at the free end of the blade and defined by an end wall and the side wall of at least one rim which extends between the leading edge and the trailing edge of the blade, and at least one cooling channel connecting said internal cooling passage to said open cavity, said cooling channel opening out at the base of the rim and the wall of the rim forming an angle relative to said end wall that is obtuse, being strictly greater than 90°. An indentation may be formed in the wall of the rim at the outlet from said cooling channel. Said blade advantageously does not include a pressure rim.

Abstract: The invention concerns a method for catalytic (cyclo)condensation of monomer isocyanates, characterised in that it comprises: a) reacting starting monomer isocyanates with a catalyst comprising a mineral or organic salt of a compound of formula (I), wherein Y? is selected among: a negatively charged oxygen atom, and a carbonaceous radical comprising a negative charge borne by an atom of column VB of the periodic table or by an oxygen atom advantageously by a nitrogen atom and whereof the bond with the silicon of formula (I) is borne by an atom of column VB of the periodic table, advantageously by a nitrogen atom; wherein R1, R2 and R3, identical or different, represent a monovalent hydrocarbon radical having advantageously 1 to 30 carbon atoms, or a precursor of said compound, at a temperature of at least 20° C. and advantageously of at least 40° C. and not more than 200° C., advantageously not more than 150° C.

Abstract: The invention concerns a method for catalytic (cyclo)condensation of monomer isocyanates, characterised in that it comprises: a) reacting starting monomer isocyanates with a catalyst comprising a mineral or organic salt of a compound of formula (I), wherein Y− is selected among: a negatively charged oxygen atom, and a carbonaceous radical comprising a negative charge borne by an atom of column VB of the periodic table or by an oxygen atom advantageously by a nitrogen atom and whereof the bond with the silicon of formula (I) is borne by an atom of column VB of the periodic table, advantageously by a nitrogen atom; wherein R1, R2 and R3, identical or different, represent a monovalent hydrocarbon radical having advantageously 1 to 30 carbon atoms, or a precursor of said compound, at a temperature of at least 20° C. and advantageously of at least 40° C. and not more than 200° C., advantageously not more than 150° C.