Combustion apparatus for a gas turbine having separate combustion and vaporization zones

Combustion chamber apparatus for a gas turbine comprising:

• a flame tube for combustion of a fuel-air mixture,
• a first fuel injection means for supplying to the flame tube a fuel-air mixture which undergoes combustion in the flame tube,
• a first chamber forming a primary combustion zone, said first chamber being separate from and outside said flame tube,
• a second chamber forming a primary vaporization zone, said second chamber being outside said flame tube, and separate from said first chamber, and,
• a second fuel injection means for supplying a fuel-air mixture to said second chamber wherein primary vaporization takes place, said second chamber being connected to said first chamber to supply the latter with vaporized fuel-air mixture which undergoes primary combustion in said first chamber, said first chamber being connected to said flame tube downstream of said first fuel injection means to supply the flame tube with primary combustion products from said primary combustion zone,
• said flame tube being of annular shape, said first and second chambers being present in a plurality of pairs arranged circumferentially around said flame tube.

A method of combustion of fuel-air mixtures in combustion chamber apparatus for a gas turbine comprising:

• vaporizing a lean fuel-air mixture in a vaporization chamber,
• supplying the vaporized fuel-air mixture to a separate combustion chamber, said combustion chamber being symmetrically formed around an axis, the vaporized fuel-air mixture being supplied eccentrically to said combustion chamber and thereby forming a rotational whirl of the fuel-air mixture in the combustion chamber around said axis,
• effecting combustion of the fuel-air mixture in the combustion chamber,
• supplying combustion products from the combustion chamber to a flame tube,
• supplying, through a fuel injection means, a second fuel-air mixture to the flame tube which is richer than the mixture supplied to the combustion chamber,
• effecting combustion of the second fuel-air mixture in the flame tube in a pilot stage, and
• effecting combustion in said flame tube, in a secondary combustion zone therein of the combustion products of the pilot stage and of the combustion chamber, the combustion products from the combustion chamber being supplied to said secondary combustion zone of said flame tube downstream of said fuel injection means in the flame tube.

A method of combustion of fuel-air mixtures in combustion chamber apparatus for a gas turbine comprising:

• vaporizing a lean fuel-air mixture in a vaporization chamber,
• supplying the vaporized fuel-air mixture to a separate combustion chamber,
• effecting combustion of the fuel-air mixture in the combustion chamber,
• supplying combustion products from the combustion chamber to a flame tube,
• supplying, through a fuel injection means, a second fuel-air mixture to the flame tube which is richer than the mixture supplied to the combustion chamber,
• effecting combustion of the second fuel-air mixture in the flame tube in a pilot stage, and
• effecting combustion in said flame tube, in a secondary combustion zone therein of the combustion products of the pilot stage and the combustion chamber, the combustion products from the combustion chamber being supplied to said secondary combustion zone of said flame tube downstream of said fuel injection means in the flame tube, and wherein said flame tube has an annular shape,
• said method further comprising:
• arranging said vaporization chamber and said combustion chamber in a plurality of pairs disposed circumferentially around the flame tube to supply combusted products from the combustion chambers of said plurality of pairs to said flame tube around the circumference thereof.