TURBOJET ENGINE LOW-PRESSURE COMPRESSOR FIRST STAGE ROTOR IMPELLER (VERSIONS) Russian patent published in 2016 - IPC F01D5/22 B01J3/00 

FIELD: engines and pumps.

SUBSTANCE: invention relates to engine building. Rotor first stage impeller, including jet turbine engine (JTE) low pressure compressor (LPC) drum-disc design shaft comprises disc equipped with slots, and blade ring, wherein disc is made in form of one-piece element including hub with central hole, web and rim, and blades each contain tail and wing with profile formed by concave pressure side and convex back, coupled by inlet and outlet edges. Disc web is made with variable in height section, conically narrowing from hub to rim with gradient of G_n thickness reducing in specified direction, equal to G_p=(δ_p.p.-δ_c.p.)/H_AV=(0.11÷0.15) [m/m], where δ_p.p. is disc web peripheral part thickness; δ_c.p. is web root part thickness; H_AV is disc web radial height between sections of connections with hub and rim. Hub is made integral with rotor shaft front bearing trunnion developed on one side to LPC inlet and made with variable diameter, gradually decreasing at least in two projections from disc web to trunnion support end section. Wheel rim outer surface is made composing internal circuit flow section axial section with axial length equal to rim generatrix projection on rotor shaft axis, and with radius increasing in LPC axial cross-section towards working fluid flow, wherein rim is connected with disc web to make front and rear circular conical flanges. Rear flange is provided with annular element made for for subsequent permanent connection with second stage disc web front flange, and grooves are uniformly spaced apart along wheel rim perimeter with angular frequency Y_u=(4.6÷6.2) [unit/rad] and are made with mutually inclined side edges, having in cross section configuration of lock joint with blade root element. Slots for fitting blade roots are uniformly spaced apart along disc rim perimeter, wherein each slot foot is located in plane parallel to rotor shaft axis, and groove bottom longitudinal axis makes with rotor shaft axis in projection on said plane angle of α blade shank installation, defined in range of values α=(16÷22)°, and root inlet and outlet edges are made diverging to peripheral blade end with gradient G_w.h. their connecting chord increase, equal to G_w.h.=(L_p.h.-L_c.h.)/H_av=(9.3÷13.3)·10^-2 [m/m], where L_p.h. is peripheral chord length connecting blade body inlet and outlet edges in conditional plane perpendicular to blade body axis; L_c.h. is same, root chord length; H_av is blade body average height.

EFFECT: invention allows to increase efficiency and increase gas-dynamic stability margin at all operation modes of compressor while increasing LPC rotor impeller service life without increase of material consumption.

19 cl, 5 dwg