Cooling system for hot parts of an aircraft engine, and aircraft engine equipped with such a cooling system

Abstract

The cooling system ( 30 ) for an aircraft engine ( 10 ) comprises a channel ( 32 ) that draws off cold air in the secondary air flow ( 200 ), and a heat exchanger ( 34 ) located in the channel ( 32 ) and in which hot air circulates. The channel ( 32 ) comprises: a supply pipe ( 322 ) and an evacuation pipe ( 326 ) fixed to the nacelle ( 324 ), an intermediate box ( 324 ) located between the supply pipe ( 322 ) and the evacuation pipe ( 326 ), fixed to the engine ( 10 ), and in which the heat exchanger ( 34 ) is placed. Application to cooling of hot parts ( 22 ) in an aircraft engine ( 10 ).

1 . Cooling system ( 30 ) for hot parts ( 22 ) of an aircraft engine ( 10 ), 
 the aircraft engine ( 10 ) being housed in a nacelle ( 24 ), a primary air flow ( 100 ) passing inside the engine and a secondary air flow ( 200 ) passing around the engine ( 10 ) inside the nacelle ( 24 ),    cooling system ( 30 ) characterised in that it comprises at least one channel ( 32 ) that draws off cold air ( 300 ) in the secondary air flow ( 200 ) and at least one heat exchanger ( 34 ) located in the channel ( 32 ) and in which hot air ( 420 ) from the primary air flow ( 100 ) circulates to be cooled before reaching ( 440 ) hot parts ( 22 ) to cool them,    and in that said at least one channel ( 32 ) comprises the following three parts: 
 a supply pipe ( 322 ) on the upstream side of said at least one heat exchanger ( 34 ), said supply pipe ( 322 ) being fixed to the nacelle ( 24 ),  
 an evacuation pipe ( 326 ) located on the downstream side of said at least one heat exchanger ( 34 ), said evacuation pipe ( 326 ) being fixed to the nacelle ( 24 ),  
 an intermediate box ( 324 ) located between the supply pipe ( 322 ) and the evacuation pipe ( 326 ) in which said at least one heat exchanger ( 34 ) is located, said intermediate box ( 324 ) being fixed to the engine ( 10 ).  
   
   
   
       2 . Cooling system ( 30 ) according to  claim 1 , characterised in that the intermediate box ( 324 ) has a longitudinal section with a profile approximately in the shape of a trapezium, in which the large base is facing the engine ( 10 ) and the small base is facing the nacelle ( 24 ).  
   
   
       3 . Cooling system ( 30 ) according to  claim 1 , characterised in that it also comprises an upstream seal between the supply pipe ( 322 ) and the intermediate box ( 324 ) and a downstream seal between the intermediate box ( 324 ) and the evacuation pipe ( 326 ).  
   
   
       4 . Cooling system ( 30 ) according to  claim 1 , characterised in that each intermediate box ( 324 ) is associated with: 
 at least one inlet duct ( 42 ), that draws in air ( 420 ) from the hot primary air flow ( 100 ), and carries it into the heat exchanger ( 34 ) to cool it, and    at least one return duct ( 44 ), that collects cooled air ( 440 ) in the heat exchanger ( 34 ) and returns to hot parts ( 22 ) of the engine ( 10 ) to cool them.    
   
   
       5 . Cooling system ( 30 ) according to  claim 4 , characterised in that each inlet duct ( 42 ) and each return duct ( 44 ) comprises an attachment flange ( 43 ) at one of its ends for fixing it onto the engine ( 10 ).  
   
   
       6 . Cooling system ( 30 ) according to  claim 5 , characterised in that at least one of the inlet ducts ( 42 ) is provided with a valve.  
   
   
       7 . Cooling system ( 30 ) according to  claim 5 , characterised in that at least one of the return ducts ( 44 ) is provided with a valve.  
   
   
       8 . Cooling system ( 30 ) according to  claim 5 , characterised in that each intermediate box ( 324 ) is associated with four inlet ducts ( 42 ) and four return ducts ( 44 ).  
   
   
       9 . Cooling system ( 30 ) according to  claim 1 , characterised in that the outlet ( 327 ) from the evacuation pipe ( 326 ) of each channel ( 32 ) opens up at the outlet from the nacelle ( 24 ) ejection nozzle ( 26 ), or beyond it on the downstream side.  
   
   
       10 . Cooling system ( 30 ) according to  claim 1 , characterised in that the outlet section ( 323 ) of the supply pipe ( 322 ) of each channel ( 32 ) is larger than its inlet section ( 321 ).  
   
   
       11 . Cooling system ( 30 ) according to  claim 1 , characterised in that the outlet section ( 327 ) of the evacuation pipe ( 326 ) of each channel ( 32 ) is identical to its inlet section ( 325 ).  
   
   
       12 . Cooling system ( 30 ) according to  claim 1 , characterised in that it comprises at least two heat exchangers ( 34 ) distributed circumferentially around the engine ( 10 ), and in that each heat exchanger ( 34 ) is placed in a separate channel ( 32 ).  
   
   
       13 . Cooling system ( 30 ) according to  claim 1 , characterised in that it comprises a single heat exchanger ( 34 ) extending around the entire circumference of the engine ( 10 ) and in that this heat exchanger ( 34 ) is placed in a single corresponding annular channel ( 32 ).  
   
   
       14 . Aircraft engine ( 10 ), characterised in that it is equipped with a cooling system ( 30 ) according to any one of  claims 1  to  13 .