Method for the arrangement of impingement cooling holes and effusion holes in a combustion chamber wall of a gas turbine

Abstract

A method for the arrangement of effusion holes and impingement cooling holes in a combustion chamber wall including: distribution of the effusion holes in the surface to be cooled in accordance with pattern, diameter and dimension selections made; distribution of the impingement cooling holes in accordance with pattern, diameter and dimension selections made; checking of the number of matches and their spacing from one another, taking into account the component and assembly tolerances; comparison with the permitted number and their minimum spacing; and, if quality requirements are not met, taking corrective actions, including selecting alternative diameters and patterns.

What is claimed is: 
     
         1 . Method for the arrangement of effusion holes and impingement cooling holes in a combustion chamber wall and in combustion chamber tiles of a gas turbine, with the combustion chamber having a combustion chamber wall provided with impingement cooling holes and combustion chamber tiles, which are arranged at a distance from the combustion chamber wall and provided with effusion holes, characterized in that the method includes the following process steps:
 1.) Stipulation of the maximum permitted number of matches, where an impingement pooling hole axis matches an effusion hole center point at a distance y, and of the minimum spacing between the matches.   2.) Selection of the pattern for the effusion holes.   3.) Stipulation of the diameter of the effusion holes.   4.) Calculation of the dimensions of the basic cell for the effusion holes, such that all holes provided fit into the surface to be cooled.   5.) Distribution of the effusion holes in the surface to be cooled in accordance with the selections made under 2. and 3.   6.) Selection of the pattern for the impingement cooling holes.   7.) Stipulation of the diameter of the impingement cooling holes.   8.) Calculation of the dimensions of the basic cell, such that all impingement cooling holes provided fit into the surface to be cooled.   9.) Selection of the alignment of the basic cell for the impingement cooling holes.   10.) Distribution of the impingement cooling holes in accordance with the selections made under 6. and 7.   11.) Checking of the number of matches and their spacing from one another, taking into account the component and assembly tolerances.   12.) Comparison with the permitted number and their minimum spacing.   13.) If the quality requirements are not met:
 a) First select another alignment of the basic cell of the impingement cooling holes and return to 10. 
 b) If this does not succeed, chose another diameter of the impingement cooling holes and return to 8. 
 c) If this does not succeed, chose another pattern and/or another basic cell of the impingement cooling holes and return to 6. 
 d) If this does not succeed, chose another effusion hole diameter and return to 4. 
 e) If this does not succeed, chose another effusion hole pattern and return to 3. 
 f) If this does not succeed, check the input data from the total of the geometric surfaces of all effusion holes, the total of the geometric surfaces of all impingement cooling holes and the surface to be cooled. 
 g) If this does not succeed. change the quality requirements. 
   
     
     
         2 . Combustion chamber wall of a gas turbine, which at least on one part of the combustion chamber wall is provided with a two-layer cooling system and designed in accordance with the method of  claim 1 . 
     
     
         3 . Combustion chamber wall in accordance with  claim 2 , characterized in that at least on one part of the combustion chamber wall the impingement cooling holes are distributed according to a different rule than that for the effusion holes, while avoiding a fixed geometric relationship between the impingement cooling holes and the effusion holes. 
     
     
         4 . Combustion chamber wall in accordance with  claim 3 , characterized in that at least on one part of the combustion chamber wall no even-numbered multiples of the number of impingement cooling holes are provided for the number of effusion holes.