Combustion chamber for gas turbines

Claim 1

A combustion chamber for a gas turbine comprising a flame tube connected with an exhaust passage at its outlet end, and connected with a prechamber at its inlet end, said flame tube having first and second flame chambers and a narrow cross-section passage connecting said first and second flame chambers, wherein there are provided air inlet openings in the periphery of said flame tube on the downstream side of said narrow cross-sectional passage, said prechamber having a fuel delivery device and a ring-shaped air inlet opening at the end away from said flame tube, and having uncontrolled air inlet openings between said fuel delivery device and said flame tube, said prechamber having cross-sectional dimensions which are a selected amount smaller than the cross-section of said flame tube to cause a stable lean flame in said flame tube at fuel-air ratios below a selected value, and to cause flame flash-back and a stable rich flame in said prechamber at higher fuel-air ratios, associated with higher turbine loads, an auxiliary combustion chamber for producing an auxiliary flame, wherein said auxiliary combustion chamber is provided with a quantity of fuel for maintaining a rich auxiliary flame, first and second passages connecting said auxiliary combustion chamber with said first and second flame chambers, and wherein there are provided means for alternately directing said auxiliary flame through one of said passages into said first flame chamber or said second flame chamber in accordance with the load condition of said gas turbine.