Combustor with a combustion region between an inner pipe and outer pipe with an ignition device upstream of the combustion region

摘要

Includes a low flow-rate region (R2) that is disposed on an upstream side of a combustion region (R1) within a second pipe (2), and that has a relatively slow flow-rate of combustion gas (G1) within the second pipe, and a flame kernel formation unit (3a) is disposed in the low flow-rate region.

主权项

1. A combustor comprising:
a first pipe through an interior of which flows combustion gas formed by mixing fuel and an oxidant and which emits the combustion gas outward in a radial direction thereof via apertures within a flame-quenching distance; a second pipe to which the combustion gas that is emitted from the apertures of the first pipe is supplied, and including a combustion region that burns the combustion gas supplied from an upstream side, and that circulates burned gas to a downstream side; and an ignition apparatus which ignites combustion gas supplied to the second pipe using a flame kernel that is formed by a flame kernel formation unit; wherein the first pipe is an inner pipe which has the combustion gas supplied from a first end, while a second end is a blocked end; the second pipe is an outer pipe which is disposed around an outer circumference of the first pipe with interposition of the combustion region, and which discharges the combustion gas from one end, while another end is a blocked end that is disposed near the second end of the first pipe; a cavity region is formed by the combustion gas emitted from the apertures of the first pipe flowing toward the one end of the second pipe through the combustion region, the cavity region being formed on the upstream side of the combustion region within the second pipe, between the blocked end of the first pipe and the blocked end of the second pipe, wherein a flow rate of the combustion gas in the cavity region is less than a flow rate of the combustion gas in the combustion region, the flame kernel formation unit is disposed in the cavity region, the flame kernel formation unit and the first pipe are disposed in series in a longitudinal direction of the first pipe, and the flame kernel formation unit is positioned so that a distance from the blocked end of the first pipe to the flame kernel formation unit is maintained to be greater than the flame-quenching distance even when the first pipe is stretched, due to thermal expansion, in the longitudinal direction of the first pipe.