Pre-Mix Combustion System for a Gas Turbine and Method of Operating of operating the same

A method for operating a gas turbine pre-mix combustion system, comprising:

• mixing a fuel with air for generating a main fuel/air mixture;
• introducing a plurality of streams of the main fuel/air mixture into a combustion zone;
• grouping the streams into a plurality of groups of streams;
• impinging at east two of the streams in the groups of streams on each other in impingement zones by introducing the at east two of the streams in opposed flow paths;
• and
• staging the impingement zones of the groups of streams in the combustion zone in a flow direction of an exhaust gas and in a direction perpendicular to the flow direction.

A pre-mix combustion system for a gas turbine, comprising

• a combustor with a combustor wall that partly surrounds a combustion zone and a plurality of groups of main mixing ducts;
• main air passages in the main mixing ducts which lead to outlet openings being open towards the combustion zone;
• and
• fuel injection openings that lead into the main air passages and connect the main air passages to a main fuel supply passage to inject a main fuel into main air flowing through the main air passages to generate a main fuel/air mixture,
• wherein locations of the outlet openings and orientations of downstream sections of the main air passages of at least two of the main mixing ducts in each of the groups are chosen such that flow paths of the main fuel/air mixture of the at least two of the main mixing ducts flowing out of the outlet openings have opposed flow paths to impinge on each other in impingement zones of the combustion zone, and
• wherein the impingement zones of the groups of the main mixing ducts are staggered in the combustion zone in flow direction of an exhaust gas and in an direction perpendicular to the flow direction.