| 摘要 |
FIELD: engines and pumps.SUBSTANCE: invention relates to engine building. Second stage rotor impeller comprises disc and blade ring. Disc is made in form of one-piece element including hub with central hole, rim and web, provided with inclined flanges for permanent connection with shaft adjacent stages mating contact elements. 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 Gthickness reducing in specified direction, equal to G=(0.05÷0.07) [m/m]. Wheel rim outer surface is made with radius increasing in LPC axial cross-section towards working fluid flow. Slots for fitting blade roots are uniformly spaced apart along disc rim perimeter and made with mutually inclined side faces, having in cross section configuration of lock joint with blade root element. Each slot longitudinal axis with rotor shaft axis in projection on arbitrary axial plane makes, normal to blade root radial axis, angle of α blade root installation defined in range of values α=(17÷25)°. Root inlet and outlet edges are made diverging to peripheral blade end with gradient Gtheir connecting chord increase, equal to G=(6.6÷9.5)∙10[m/m].EFFECT: invention allows to increase efficiency and increase GDS margin at all operation modes of compressor while increasing LPC rotor impeller service life without increase of material consumption.21 cl, 5 dwg |
