Gas turbine combustor with flame forming air supply holes

摘要

A gas turbine combustor has a premixing burner (76, 77) for premixing fuel with air and jetting the mixed gas into a combustion chamber (5), wherein a conical flame (43) can be formed and the metal temperature at a liner (10) of the combustion chamber (5) and a burner end face (30) can be reduced. A cylindrical guide (36) attached to an outer circumferential portion of the burner end face (30) is provided with air supply holes (38). A distance interval D1 defined between adjacent air supply holes (38) and a distance interval D2 defined between each air supply hole (38) and the burner end face (30) are each made narrower than the quenching distance in the premixed gas jetted from the premixing burner (76, 77). Particularly, the distance intervals D1 and D2 are both smaller than 1 cm, value corresponding to the quenching distance of 5% natural gas in air at typical gas turbine pressures and temperatures.