Rim seal for a gas turbine engine

Abstract

The rim seal is positioned in an annular space between blades and a non-rotating adjacent structure in a gas turbine engine. The rim seal is connectable to the non-rotating structure and is made of an abradable material.

1 . A rim seal for an annular space between blade platforms and a non-rotating adjacent structure in a gas turbine engine, the rim seal being connectable to the non-rotating structure and made of an abradable material. 
   
   
       2 . The rim seal as defined in  claim 1  wherein each blade platform has a side protruding portion in engagement with the abradable material. 
   
   
       3 . The rim seal as defined in  claim 2  wherein a cold gap is provided between the protruding portion and the rim seal at ambient conditions, the cold gap being designed to close due to thermal expansion during operation of the gas turbine engine. 
   
   
       4 . The rim seal as defined in  claim 1  wherein the non-rotating structure is made of sheet metal the structure having an end folded radially inwards, the abradable seal being connected to the end. 
   
   
       5 . The rim seal as defined in  claim 4  wherein the non-rotating structure comprises a seal-holding bracket secured to the end. 
   
   
       6 . An annular abradable rim seal for mitigating combustion gas ingestion on a side of blades in a gas turbine engine, the seal having an outer peripheral portion configured and disposed to be at least partially in friction engagement with blade platforms during operation of the engine. 
   
   
       7 . The rim seal as defined in  claim 6  wherein a cold gap is provided between the blades and the rim seal at ambient conditions, the cold gap being designed to close due to thermal expansion during operation of the gas turbine engine. 
   
   
       8 . The rim seal as defined in  claim 6  wherein the non-rotating structure comprises a seal-holding bracket secured to a side thereof. 
   
   
       9 . A method of sealing an annular space between blade platforms and a non-rotating structure immediately adjacent to the blade platforms in a gas turbine engine, the method comprising:
 securing to the non-rotating structure an abradable annular seal provided in the annular space; and   operating the gas turbine engine to carve a notch in the seal with the side of the blades.