Patent ID: 6709239
Filing Date: 2004-03-23
Classification: F01D,Y10S

Abstract:
An improved three dimensional blade for axial steam turbine comprising a leading edge with an inlet flow angle and a trailing edge with an outflow angle, a pressure face between the leading edge and the trailing edge, a suction face between the leading edge and the trailing edge on the opposite side of the pressure face and a chord, which is the line connecting the leading edge and the trailing edge through a stagger angle formed at the intersection of said chord and a U-axis coinciding with the circumferential direction of the blade, wherein the blade is made of varying cross-sections of profiles and leaned such that the centre of gravity in a mid-section of each varying cross-section is shifted opposite to the direction of blade rotation and the blade sections from hub to tip are twisted in a gradual manner, andwherein the said blade is formed by stacking three basic profiles with lagrangian parabolic distribution and leaning them as per a design curve.