Swirling-flow burner

Claim 1

A swirling-flow burner comprising: a burner tube and an oxidizer supply tube concentric with and spaced from the burner tube, defining an annular fuel gas conduit between the tubes, the oxidizer supply tube and the fuel gas conduit having separate inlet ends and separate outlets ends: a fuel gas injector connected to the outlet end of the fuel gas conduit, the fuel gas injector having a substantially U-shaped cross section around a common axis of symmetry of the burner tube and the injector and having an annular outlet directed inwardly towards the axis and a gas mixing zone; an oxidizer injector connected to the outlet end of the oxidizer supply tube and having an axis of symmetry common with the fuel gas injector, wherein the outlet of the oxidizer injector as directed towards the gas mixing zone; and a static swirler provided in the oxidizer injector for producing a swirling movement of the oxidizer around the axis before the oxidizer is discharged from the oxidizer injector, wherein the static swirler includes a partition dividing the flow of oxidizer into an upstream and a downstream section, the partition being provided with at least one passageway for the passage of the oxidizer from the upstream to the downstream section, wherein the passageway forces the flow direction of oxidizer from a direction parallel with the axis of symmetry upstream of the partition to a direction transversely thereto and tangentially in relation to the axis downstream of the partition, thereby forming a rotating flow of oxidizer around the axis, and wherein the fuel gas injector has a substantially planar internal surface surrounding the fuel gas outlet for directing a fuel gas flow mainly perpendicularly against the flow of oxidizer in the gas mixing zone.