Patent ID: 6540478
Filing Date: 2003-04-01
Classification: F01D,F04D

Abstract:
Blade row arrangement for turbo-engines, in an axial-flow coaxial construction, comprising:two guide blade rows situated in a fixed axial and circumferential position relative to one another, said guide blade rows having a different number of blades and each having a constant pitch angle between respective blades, and a moving blade row rotatably arranged between the guide blade rows, the upstream guide blade row having a flow-off direction with an axial and circumferential component comparable with respect to size, wherein the blades of the upstream guide blade row, in one of a first cohesive partial area T1 of the guide blade row and a partial area T1 distributed in several separate sectors along a row circumference, successively have an axial offset &Dgr;m of the same amount as well as in the same direction, wherein the axial offset &Dgr;m, as a function of a blade number ratio Z1/Z2 of the first and the second guide blade rows is selected such that, at Z1>Z2, the axial offset &Dgr;m increases an effective flow-off cross-section Aeff between the blades and such that, at Z12 reduces the flow-off cross-section, and wherein the blades of the upstream guide blade row, in one of a second cohesive partial area T2 of the guide blade row and a second partial area T2 of the guide blade row distributed in several separate sectors along the row circumference, successively have an axial offset &Dgr;n which has the same size or varies and is oppositely directed in relation to &Dgr;m.