Cooling method and apparatus

Abstract

Apparatus for adaptive cooling comprising a first component having at least one aperture extending therethrough with a sacrificial component positioned within the at least one aperture. The first component is operable at a maximum duty temperature and the sacrificial component has a melting or sublimation point below the maximum duty temperature of the first component. The sacrificial component defines an effective aperture the size of which may be increased if, in use, the sacrificial component is subjected to a temperature between the melting or sublimation point of the sacrificial component and the maximum duty temperature of the first component.

1 . A method of adaptive cooling, the method comprising the steps
 providing a first component having at least one aperture extending therethrough, the first component operable at a maximum duty temperature;   providing a sacrificial component having a melting or sublimation point below the maximum duty temperature of the first component and positioned within the at least one aperture, thereby defining an effective aperture;   applying heat such that the temperature of the sacrificial component is raised to a temperature between its melting or sublimation point and the maximum duty temperature of the first component wherein the effective aperture increases in size.   
     
     
         2 . A method of adaptive cooling according to  claim 1 , further comprising the step of passing a flow of coolant through the effective aperture. 
     
     
         3 . A method according to  claim 1 , wherein as the effective aperture increases in size the temperature of the sacrificial component is reduced by the flow of coolant to a temperature below the melting or sublimation point of the sacrificial component. 
     
     
         4 . A method according to  claim 1 , wherein the first component is a wall of a combustion chamber. 
     
     
         5 . A method according to  claim 4 , wherein the combustion chamber is a gas turbine combustion chamber. 
     
     
         6 . A method according to  claim 4 , wherein the combustion chamber is a combustion chamber in an afterburner. 
     
     
         7 . A method according to  claim 1  wherein the first component is a wall of an exhaust duct. 
     
     
         8 . A method according to  claim 1 , wherein the coolant is air.