A premixing device includes: a gas flow passage forming member in which an x direction is used as an axial length direction, and a Venturi-shaped gas flow passage into which air can flow in from the outside is formed inside; and a blade portion positioned in the gas flow passage, extending in a y direction, and equipped with a fuel gas outlet. The blade portion includes first and second blade portions spaced apart from each other in a z direction, and an air flow path near the center through which a part of the air flows is formed between these first and second blade portions. At least one of a pair of surfaces of the first and second blade portions facing each other is equipped with an inner bulging portion that bulges in the z direction so as to squeeze a part of the air flow path near the center.

A fuel burner includes a tube extending along a centerline from a first end to a second end and having an outer surface and an inner surface defining a central passage. The central passage is supplied at the first end with a mixture of air and combustible fuel pre-mixed upstream of the tube. The second end is closed by an end wall in a fluid-tight manner. The tube has fluid directing structure for directing the pre-mixed mixture radially outward from the central passage to an exterior of the tube such that flames exiting adjacent fluid directing structures extend towards and impinge one another.

A fuel burner includes a tube extending along a centerline from a first end to a second end and having an outer surface and an inner surface defining a central passage. The central passage is supplied at the first end with a mixture of air and combustible fuel pre-mixed upstream of the tube. The second end is closed by an end wall in a fluid-tight manner. The tube has fluid directing structure for directing the pre-mixed mixture radially outward from the central passage to an exterior of the tube such that flames exiting adjacent fluid directing structures extend towards and impinge one another.

A high efficiency heating apparatus for heating fluids and cooking mediums, such as oil or shortening within a fryer, includes a natural draft (non powered) combustion chamber that is affixed to an exterior surface of a fry tank.

A high efficiency heating apparatus for heating fluids and cooking mediums, such as oil or shortening within a fryer, includes a natural draft (non powered) combustion chamber that is affixed to an exterior surface of a fry tank.

A burner gas supply apparatus for increasing flame turbulence, the apparatus comprising a conduit having a characteristic width, W, defined by an inner surface having a circumferential direction and an axial direction, the axial direction terminating in a nozzle defining a nozzle exit plane and having a characteristic dimension, d, where d<=W; and three bluff bodies each with a characteristic dimension, D.sub.bb-i, projecting a length, L.sub.i into the conduit from the inner surface, and an axial spacing X.sub.i between adjacent bluff bodies (between the downstream bluff body and the nozzle exit plane in the case of X.sub.1) wherein 0.5<=L.sub.i/W<=1 and wherein X.sub.i/D.sub.bb-i<=30.

A micro-mixer capable of effectively mixing compressed air supplied from a compressor to a combustor and fuel supplied from a fuel nozzle, and a combustor including the same are provided. The micro-mixer includes a mixing passage including an inlet and an outlet, a fuel supply passage extending from one inner wall to the other inner wall of the mixing passage, and a fuel supply port formed in the fuel supply passage to supply fuel to the mixing passage.

Provided are a burner and a water heater. The burner comprises multiple flame splitters, and each of the flame splitters is provided with at least three ejector pipes, and the multiple flame splitters are arranged parallel to one another; a fastener penetrates through the multiple flame splitters and connects the multiple flame splitters into a flame row; and compressing members are arranged at end parts where the fastener extends relative to the flame row, and the compressing members compress the flame row. The burner is integrally installed, easy to operate and firmly fixed, the combustion intensity can also be increased, the emission of nitrogen oxides is reduced, and the safety of use is ensured.

A method heats a furnace process chamber with the combustion of fuel gas. The method heats the process chamber in a preheat mode when the temperature of the process chamber is below the autoignition temperature of the fuel gas. The preheat mode forms preheated combustion air by directing the combustion air through a regenerative bed. A stream of the preheated combustion air is directed into the process chamber in a condition unmixed with fuel gas. The preheat mode also forms a fuel rich mixture of the fuel gas and unheated combustion air. The fuel rich mixture is directed into the process chamber adjacent to the stream of preheated combustion air.

A burner assembly includes a spreader and a burner cap coupled to the spreader. The burner cap includes a sheet metal base bounded by a peripheral lip and a sheet metal top extending over the sheet metal base to define a gap and having a peripheral rim that wraps about at least a portion of the peripheral lip. The sheet metal base defines at least one port configured to allow air to flow into and out of the gap.