Patent ID: 6234754
Filing Date: 2001-05-22
Classification: B22C,F01D,F05D,Y02T

Abstract:
For an axial flow rotary machine which includes a turbine section having an annular flowpath for working medium gases and a rotor assembly having an axis of rotation Ar, a rotor blade having an airfoil disposed about a spanwise axis, the rotor blade having an opening which adapts the airfoil to be in flow communication with a source of cooling fluid under operative conditions, the airfoil having a leading edge region and a trailing edge region, the airfoil having an inner portion, an outer portion, and a mid-span portion that extends from the inner portion to the outer portion, the airfoil having a suction wall extending chordwisely and spanwisely about one side of the airfoil from the leading edge region to the trailing edge region and having a suction wall lip disposed in the trailing edge region, the airfoil having a pressure wall extending chordwisely and spanwisely about the opposite side of the airfoil from the leading edge region to the trailing edge region, the pressure wall being spaced laterally from the suction wall leaving a cavity for cooling fluid therebetween in flow communication with said opening and a flowpath for cooling fluid which extends through the trailing edge region to the suction wall lip, the pressure wall including a pressure wall lip, and wherein the suction wall lip and pressure wall lip define a trailing edge disposed in the trailing edge region, which comprises:an internal passage for the flowpath for cooling fluid which extends spanwisely and is in flow communication with the opening for cooling fluid;an array of flow dividers in flow communication with the internal passage for discharging cooling fluid into the working medium flowpath, each flow divider having at least a portion which extends from the pressure wall to the suction wall, each divider includinga flow divider leading edge,a first converging sidewall which faces spanwisely inwardly and which is angled away from the direction of flow between flow dividers with an angle .alpha. as measured with respect to a line parallel to the axis Ar and a second converging sidewall which faces spanwisely outwardly and which is angled away from the direction of flow between flow dividers with an angle .beta. as measured with respect to a line parallel to the axis Ar, the converging sidewalls forming a pair of sidewalls, the pair of converging sidewalls converging in the downstream direction such that spanwisely facing sidewalls of adjacent dividers diverge to define a diffusing section between adjacent dividers;wherein the diffusing section extends from upstream to at least one of said lips; and, wherein the angle .alpha. of the inwardly facing sidewall is greater than the angle .beta. of the outwardly facing sidewall; and, wherein the inwardly facing sidewall under operative conditions exerts a centripetal force on the flow enabling the first sidewall to provide a greater amount of diffusion without separation of the flow than the outwardly facing second sidewall.