Combustor and combustion apparatus

A combustor including a premixing type combustion burner which has an atomizer for atomizing a liquid fuel in combustion air from an upstream direction, and an evaporation chamber in which the atomized fuel is evaporated and premixed with the combustion air to form a premixture which is ejected from an outlet of said premixing type combustion burner at a downstream end of said evaporation chamber

• said atomizer comprising an inner shell having an inner peripheral surface to which said liquid fuel is supplied, an outer shell defining a passage in which combustion air can substantially straightly flow in a downstream direction between the outer shell and an outer peripheral surface of said inner shell, and a swirling-flow guide plate for swirling combustion air passed into the inner shell, while directing the combustion air in the inner shell in a downstream direction;
• and
• said combustor further including a resistor abruptly increasing in width in a downstream direction and provided substantially downstream of the center of the swirling flow and in the vicinity of said outlet of said premixing type combustion burner for providing a resistance to the premixture ejected from said premixing type combustion burner and forming downstream of said resistor a circulating flow of combustion gas produced by combustion of said premixture, which circulating flow flows in upstream and downstream directions.

A gas turbine apparatus comprising:

• a combustor including a premixing type combustion burner which has an atomizer for ejecting a liquid fuel together with combustion air to atomize the liquid fuel and an evaporation chamber in which the atomized fuel is evaporated and premixed with the combustion air to form a premixture, wherein
• said atomizer is comprised of an inner shell, to an inner peripheral surface of which said liquid fuel is supplied, an outer shell defining a passage in which the combustion air can flow substantially straightly between the outer shell and an outer peripheral surface of said inner shell, and a swirling-flow guide plate for swirling combustion air passed into the inner shell, while directing the combustion air in the inner shell in a downstream direction, and
• said combustor further includes a resistor abruptly increasing in width in a downstream direction and provided substantially downstream of the center of the swirling flow and in the vicinity of an outlet of said premixing type combustion burner for providing a resistance to a premixture ejected from said premixing type combustion burner and a circulating flow of combustion gas produced by combustion of said premixture downstream of said resistor;
• and
• a gas turbine adapted to be driven by an exhaust gas discharged from said combustor.

A combustion process for burning a fuel-air premixture after previous mixing of a liquid fuel with combustion air and ejecting said premixture from an outlet of a burner, comprising the steps of:

• forming, at a location upstream from the outlet of the burner, a swirling flow of said combustion air, which flow swirls while running in a downstream direction;
• forming a flow of said combustion air around said swirling flow, which flow runs straightly in the downstream direction;
• supplying said liquid fuel to a boundary between said swirling flow and said straightly running flow to premix said liquid fuel with said combustion air;
• and
• ejecting a mixture resulting from the premixing of said liquid fuel with said swirling and straightly running combustion air flows from the burner outlet to burn said mixture;
• and circulating a combustion gas produced from such combustion in the vicinity of said burner outlet substantially downstream of the center of swirling of said swirling flow.