TURBOJET LOW-PRESSURE COMPRESSOR ROTOR IMPELLER (VERSIONS) Russian patent published in 2015 - IPC F04D29/32 

FIELD: engines and pumps.

SUBSTANCE: turbojet low-pressure compressor rotor second stage wheel comprises the disc with hub, central bore, web and ring as well as working blades convexo-concave in cross-section. Every said blade comprises the root and butt. Said ring is connected with disc web to make two different-arm conical flanges inclined to conical flange flow vector. Total equal-arm part of the flange width has the grooves whereto blade roots are fitted. Ring flange cantilever sections extending beyond the slits are developed to contact with mating shelves of the previous and next stages, Longitudinal axes of every slit makes with the impeller axis in the projection on conditional axial plane perpendicular to the root radial axis the angle α₀ of root setting making α₀ = (21÷27)°. Note here that the chord of the root side edges in the blade root zone makes with the rotor projection the root setting angle α_k increasing in the root radial height with the root twist gradient G_r.t = (159.2÷245.8) [degree/m].

EFFECT: higher efficiency and longer life under all operating conditions of the compressor second stage impeller without increase in disc material input.

9 cl, 5 dwg