Forward swept rotor blade
AssigneeGeneral Electric Company
InventorsAspi R. Wadia, Peter N. Szucs, Padmakar M. Niskode, Pamela A. Battle
Life of this patent
Estimating the term…
Abstract
A rotor blade includes a root, tip, leading edge, trailing edge, forward surface, and aft surface, and a pitch section disposed equidistantly between the root and tip. The blade has a forward sweep from at least the pitch section to the blade tip relative to incoming streamsurfaces of a fluid flowable over the blade.
Claims20
A rotor blade for a gas turbine engine compressor including a plurality of said rotor blades spaced circumferentially around a rotor hub, coaxially about a longitudinal centerline axis, and radially inwardly of an annular casing for channeling and compressing air, said rotor blade comprising:
- a root joinable to said rotor hub;
- a tip;
- a leading edge extending from said root to said tip;
- a trailing edge extending from said root to said tip;
- a forward surface extending from said root to said tip and between said leading edge and said trailing edge, and facing in a direction of rotation of said blade about said centerline axis;
- an aft surface extending from said root to said tip and between said leading edge and said trailing edge on an opposite side of said blade and facing in a direction opposite to said blade rotation direction;
- a pitch section disposed equidistantly between said root and tip;
- and
- said blade extending generally radially outwardly from said hub along a radial axis disposed perpendicularly to said centerline axis and including a forward aerodynamic sweep from at least said pitch section to said tip relative to an incoming streamsurface of said air flowable over said blade for reducing aerodynamic losses due to boundary layer accumulation at said blade tip, said sweep being represented by a sweep angle S wherein:
- ##EQU2## and wherein, .rho.=meridional angle, arctan (V.sub.r V.sub.a), and V.sub.r is the component of a streamline velocity along said radial axis, and V.sub.a is the component of said streamline velocity along an axial axis extending parallel to said centerline axis;
- .beta.=cylindrical air angle, arctan V.sub.u /V.sub.a), and V.sub.u is the component of said streamline velocity along a circumferential u-axis indicating direction of rotation of said blade;
- .mu.=local axial tilt angle of a longitudinally extending portion of said blade in an a-r plane relative to said radial axis;
- and
- .eta.=local tangential lean angle of said longitudinally extending portion of said blade in a u-r plane relative to said radial axis.
Dependencies are inferred from the claim text.