Component with diagonally extending recesses in the surface and process for operating a turbine

Abstract

The invention is related to a component of a turbine machine with diagonally extending recesses in the surface of the component. Thermally stressed components of a turbine machine can be protected against excessive heat input by active cooling or by applying thermal insulation layers. The invention increases the effect by providing diagonally extending slots in the surface of the component.

1 .- 16 . (canceled) 
   
   
       17 . A component of a turbomachine having a medium flowing over the component in a direction of flow, comprising:
 an outer surface; and   a recess presented within a layer on the component that extends through a longitudinal direction from a base of the recess to the outer surface at an angle not perpendicular with respect to the outer surface.   
   
   
       18 . The component as claimed in  claim 17 , wherein the longitudinal direction extends in a plane of a side wall of the component. 
   
   
       19 . The component as claimed in  claim 17 , wherein the angle is less than 85° or greater than 95°. 
   
   
       20 . The component as claimed in  claim 17 , wherein the recess is elongated in a plane of the outer surface transverse with respect to the direction of flow. 
   
   
       21 . The component as claimed in  claim 17 , wherein the recess is present in a ceramic layer on the component. 
   
   
       22 . The component as claimed in  claim 17 , wherein the recess is present in an outermost layer on the component. 
   
   
       23 . The component as claimed in  claim 22 , wherein a penetration depth of the recess perpendicular with respect to the outer surface is from 10% to 120% of a layer thickness of the outermost layer. 
   
   
       24 . The component as claimed in  claim 23 , wherein the penetration depth is from 10% to 90% of the layer thickness of the outermost layer. 
   
   
       25 . The component as claimed in  claim 23 , wherein the penetration depth is from 50% to 80% of the layer thickness of the outermost layer. 
   
   
       26 . The component as claimed in  claim 17 , wherein the recess is a parallelogram and has edges extending in parallel to the outer surface in a cross section. 
   
   
       27 . The component as claimed in  claim 17 , wherein the component has cooling holes in a region of the outer surface with the recess. 
   
   
       28 . The component as claimed in  claim 17 , wherein the component is a turbine component. 
   
   
       29 . The component as claimed in  claim 28 , wherein the component is a turbine guide vane or rotor blade of a gas turbine. 
   
   
       30 . A component of a turbomachine having a medium flowing over the component in a direction of flow, comprising:
 an outer surface; and   a recess presented within a layer on the component that extends through a longitudinal direction from a base of the recess to the outer surface at an angle not perpendicular with respect to the direction of flow.   
   
   
       31 . The component as claimed in  claim 30 , wherein the angle is less than 85° or greater than 95°. 
   
   
       32 . The component as claimed in  claim 31 , wherein the angle is less than 80°. 
   
   
       33 . The component as claimed in  claim 31 , wherein the angle is greater than 100°. 
   
   
       34 . A method for operating a turbine, comprising:
 flowing a medium over a component of the turbine in a direction of flow;   presenting a recess within a layer on the component; and   extending the recess through a longitudinal direction from a base of the recess to an outer surface of the component at an angle not perpendicular with respect to the outer surface.