Gas turbine engine component with cusped, lobed cooling hole

Abstract

A component for a gas turbine engine includes a wall and a cooling hole. The wall has a first surface and a second surface. The second surface is exposed to hot gas flow. The cooling hole extends through the wall. The cooling hole includes a metering section extending from an inlet in the first surface of the wall to a transition, a diffusing section extending from the transition to an outlet in the second surface of the wall, a cusp on the transition, and a first longitudinal ridge extending along the diffusing section between the transition and the outlet. The first longitudinal ridge divides the diffusing section into first and second lobes.

1 . A component for a gas turbine engine, the component comprising:
 a wall having a first surface and a second surface, wherein the second surface is exposed to hot gas flow; and   a cooling hole extending through the wall, the cooling hole comprising:
 a metering section extending from an inlet in the first surface of the wall to a transition; 
 a diffusing section extending from the transition to an outlet in the second surface of the wall; 
 a cusp on the transition; and 
 a first longitudinal ridge extending along the diffusing section between the transition and the outlet, wherein the first longitudinal ridge divides the diffusing section into first and second lobes. 
   
     
     
         2 . The component of  claim 1 , wherein the cooling hole extends through the wall along an axis, and wherein the first longitudinal ridge extends away from a downstream surface of the cooling hole toward the axis. 
     
     
         3 . The component of  claim 1 , wherein the cusp extends from the transition along the metering section of the cooling hole toward the inlet. 
     
     
         4 . The component of  claim 3 , wherein the cusp extends to the transition and the longitudinal ridge extends from the cusp at the transition along the diffusing section toward the outlet. 
     
     
         5 . The component of  claim 4 , and further comprising:
 a third lobe positioned between the first and second lobes, wherein the first longitudinal ridge divides the first lobe from the third lobe; and   a second longitudinal ridge dividing the second lobe from the third lobe.   
     
     
         6 . The component of  claim 5 , wherein the third lobe terminates in a transition region extending from the first and second longitudinal ridges to a trailing edge of the outlet. 
     
     
         7 . The component of  claim 5 , further comprising:
 a first transition region extending from the first longitudinal ridge to a trailing edge of the outlet; and   a second transition region extending from the second longitudinal ridge to the trailing edge of the outlet.   
     
     
         8 . The component of  claim 1 , wherein the outlet comprises:
 a trailing edge that is substantially straight along the second surface of the wall.   
     
     
         9 . The component of  claim 1 , wherein the outlet comprises:
 a trailing edge that is substantially convex.   
     
     
         10 . The component of  claim 1 , wherein the cusp tapers as it extends from the transition to the inlet. 
     
     
         11 . The component of  claim 1 , wherein the wall forms one of a pressure surface, a suction surface or a platform surface of an airfoil. 
     
     
         12 . A gas turbine engine component comprising:
 a flow path wall having a first surface and a second surface, wherein the second surface is exposed to working fluid flow;   an inlet formed in the first surface of the flow path wall;   a metering section extending from the inlet to a transition;   a diffusing section extending from the transition to an outlet in the second surface;   a cusp formed on the transition; and   a first longitudinal ridge extending along the diffusing section from the transition toward the outlet, wherein the first longitudinal ridge separates the diffusing section into first and second lobes.   
     
     
         13 . The gas turbine engine component of  claim 12 , wherein the cusp extends from the transition along the metering section toward the inlet. 
     
     
         14 . The gas turbine engine component of  claim 13 , wherein the first longitudinal ridge is a single longitudinal ridge extending from the cusp at the transition, the first longitudinal ridge extending toward the outlet to divide the diffusing section into the first and second lobes. 
     
     
         15 . The gas turbine engine component of  claim 13 , and further comprising:
 a third lobe positioned between the first and second lobes, wherein the first longitudinal ridge divides the first lobe from the third lobe; and   a second longitudinal ridge dividing the second lobe from the third lobe.   
     
     
         16 . The gas turbine engine component of  claim 15 , wherein the third lobe terminates in a transition region extending from the first and second longitudinal ridges to a trailing edge of the outlet. 
     
     
         17 . The gas turbine engine component of  claim 13 , wherein the cusp tapers as it extends from the transition to the inlet. 
     
     
         18 . The gas turbine engine component of  claim 12 , wherein the outlet comprises:
 a trailing edge that is substantially straight along the second surface of the wall.   
     
     
         19 . The gas turbine engine component of  claim 12 , wherein the outlet comprises:
 a trailing edge that is substantially convex.   
     
     
         20 . A turbofan engine comprising the gas turbine engine component of  claim 12 .