Societe Nationale D'etude Et De Construction De Moteurs D'aviation

Societe Nationale D'etude Et Moteurs D'aviation 's.n.e.c.m.a.'

Jean-Francois R Imbault

Carmen Miraucourt

Philippe M Gastebois

Remy P Ritt

Roland R Mestre

A turbomachine rotor includes a disk having a plurality of annular ribs projecting from its periphery to define a plurality of annular grooves, and a plurality of blades, preferably made of composite material, evenly distributed around the periphery of the disk, each blade having a notched root defining heels which fit into the grooves of the disk and which are divided into two groups, one group being offset on the pressure side of the blade and the other group being offset on the suction side so that the heels of the second group align with the heels of the first group of an adjacent blade, the blades being fixed to the disk by pins which extend through the aligned heels of adjacent blades and the ribs of the disk. Each blade is thus secured by two pins, and each pin helps to secure two blades.

Turbomachine rotor with blades secured by pins

A turbine rotor has composite ceramic blades each having a bulb-shaped root with planar flanks which define an angle of convergence between them not exceeding ten degrees, and by which the root is held in a dovetail section socket in the periphery of the rotor disc by means of wedge-shaped members also disposed in the socket on opposite sides of the root. Each wedge-shaped member is part of an element including a platform which is disposed adjacent the curved portion of the blade radially outwards of the socket and which is joined to the wedge-shaped member by an integral strut. The platforms of all of the elements extend in a circumferential direction and combine to define a continuous ring forming part of the inner boundary of the gas flow path through the turbine.

Turbine rotor

A turbine ring assembly is mounted on an annular carrier secured to the irior of the casing of a turbine and includes a succession of contiguous sectors of a ceramic abradable material. The sectors have grooves in which support fingers are engaged rigid with an annular member connected to the casing of the turbine. The sectors are thereby held in an annular configuration and the support fingers are so located in the grooves as to provide a screen to prevent reintroduction of hot gases.

Growing community of inventors

Ponthierry, France

Jean-Francois R Imbault