Combustion Apparatus

Abstract

A combustion apparatus comprising: a device for mixing a fuel with an oxidant; a combustion chamber in which combustion of the fuel/oxidant mix takes place; a pre-chamber located between the device and the combustion chamber; and means for supplying a gas to the pre-chamber so as to form a film of gas on the interior surface of the pre-chamber so as to prevent a combustion flame from the combustion chamber attaching itself to this interior surface damaging the pre-chamber, the supply of gas to the pre-chamber being such that where the gas first reaches the interior surface of the pre-chamber it forms a substantially continuous film of gas over this interior surface.

1 .- 10 . (canceled) 
   
   
       11 . A combustion apparatus comprising:
 a fuel mixing device that mixes a fuel with an oxidant;   a combustion chamber where combustion of the fuel/oxidant mixture takes place;   a pre-chamber arranged between the fuel mixing device and the combustion chamber; and   a gas supply device that supplies a gas to the pre-chamber such that a film of gas is formed on the interior surface of the pre-chamber so as to prevent a combustion flame from the combustion chamber attaching itself to the pre-chamber interior surface and damaging the pre-chamber, wherein the supply of gas to the pre-chamber is such that where the gas first reaches the interior surface of the pre-chamber it forms a substantially continuous film of gas over the pre-chamber interior surface.   
   
   
       12 . The apparatus according to  claim 11 , wherein the gas supply device comprises a swirler for creating a swirling flow of the gas that travels over the interior surface of the pre-chamber to the combustion chamber. 
   
   
       13 . The apparatus according to  claim 12 , wherein the swirler comprises a plurality of slots for guiding the gas, the slots being arranged in a circle and extending generally radially inwardly. 
   
   
       14 . The apparatus according to  claim 13 , wherein the swirler comprises an annular base plate and a plurality of wedge pieces arranged circumferentially spaced around the annular base plate so as to form between adjacent wedge pieces the slots for guiding the gas, the wedge pieces being set back from the radially inner edge of the annular base plate thereby to define an annular ledge on the annular base plate immediately radially outward of the radially inner edge. 
   
   
       15 . The apparatus according to  claim 14 , further comprising an annular closing plate secured to the swirler such that one side of the annular closing plate forms a wall of the slots, the wedge pieces being set back from the radially inner edge of the annular closing plate thereby to define an annular ledge on the annular closing plate immediately radially outward of the radially inner edge of the annular closing plate. 
   
   
       16 . The apparatus according to  claim 15 , wherein the swirler is arranged between the device and the pre-chamber, and the swirler meets the pre-chamber by way of a smooth shoulder formed between the annular ledge on the annular base plate of the swirler and the interior surface of the pre-chamber. 
   
   
       17 . The apparatus according to  claim 13 , wherein the gas supplying device is arranged between the fuel mixing device and the pre-chamber. 
   
   
       18 . The apparatus according to  claim 17 , wherein the fuel mixing device comprises a swirler for creating a swirling mix of the fuel and oxidant that travels along the pre-chamber to the combustion chamber. 
   
   
       19 . The apparatus according to  claim 18 , wherein the oxidant is air and the gas is air. 
   
   
       20 . A gas turbine engine, comprising:
 a compressor section that receives a working fluid and produces a compressed working fluid;   a combustion section that receives the compressed working fluid and provides a hot working fluid, wherein the combustion section comprises:
 a fuel mixing device that mixes a fuel with a majority portion of the compressed working fluid; 
 a combustion chamber where combustion of the fuel/working fluid mixture takes place; 
 a pre-chamber arranged between the fuel mixing device and the combustion chamber; and 
 a supply device that supplies a minority portion of the compressed working fluid to the pre-chamber such that a film of gas is formed on the interior surface of the pre-chamber so as to prevent a combustion flame from the combustion chamber attaching itself to the pre-chamber interior surface and damaging the pre-chamber, wherein the supply of gas to the pre-chamber is such that where the gas first reaches the interior surface of the pre-chamber it forms a substantially continuous film of gas over the pre-chamber interior surface. 
   a turbine section that expands the hot working fluid to extract mechanical energy.   
   
   
       21 . The gas turbine engine according to  claim 20 , wherein the gas supply device comprises a swirler for creating a swirling flow of the gas that travels over the interior surface of the pre-chamber to the combustion chamber. 
   
   
       22 . The gas turbine engine according to  claim 21 , wherein the swirler comprises a plurality of slots for guiding the gas, the slots being arranged in a circle and extending generally radially inwardly. 
   
   
       23 . The gas turbine engine according to  claim 22 , wherein the swirler comprises an annular base plate and a plurality of wedge pieces arranged circumferentially spaced around the annular base plate so as to form between adjacent wedge pieces the slots for guiding the gas, the wedge pieces being set back from the radially inner edge of the annular base plate thereby to define an annular ledge on the annular base plate immediately radially outward of the radially inner edge. 
   
   
       24 . The gas turbine engine according to  claim 23 , further comprising an annular closing plate secured to the swirler such that one side of the annular closing plate forms a wall of the slots, the wedge pieces being set back from the radially inner edge of the annular closing plate thereby to define an annular ledge on the annular closing plate immediately radially outward of the radially inner edge of the annular closing plate. 
   
   
       25 . The gas turbine engine according to  claim 24 , wherein the swirler is arranged between the device and the pre-chamber, and the swirler meets the pre-chamber by way of a smooth shoulder formed between the annular ledge on the annular base plate of the swirler and the interior surface of the pre-chamber. 
   
   
       26 . The gas turbine engine according to  claim 22 , wherein the gas supplying device is arranged between the fuel mixing device and the pre-chamber. 
   
   
       27 . The gas turbine engine according to  claim 26 , wherein the fuel mixing device comprises a swirler for creating a swirling mix of the fuel and oxidant that travels along the pre-chamber to the combustion chamber. 
   
   
       28 . The gas turbine engine according to  claim 27 , wherein the oxidant is air and the gas is air.