The purpose of the present invention is to provide a combustion device for improving a turndown ratio, which is capable of stably implementing a combusted state in a low-output load region by improving a turndown ratio of a burner. To this end, the present invention provides the combustion device having a premixing chamber (300) which is connected to an air supply tube (100) and a gas supply tube (200), and which has a space for premixing air and gas provided therein, wherein the space for premixing the air and gas supplied from the air supply tube (100) and the gas supply tube (200) is divided into multiple stages of a venturi structure in the premixing chamber (300), and the discharging direction of the gas discharged inside the premixing chamber (300) through the gas supply tube (200) is formed in parallel to the flow direction of the gas supplied inside the premixing chamber (300) through the air supply tube (100).

A burner comprises a tubular diffuser wall and an inlet passage of a gas mixture in the diffuser wall, as well as a distribution diaphragm having a distribution opening which forms a central passage section and a plurality of peripheral passage sections, in the shape of rays or branches, extending from the central passage section towards the diffuser wall, and in which the peripheral passage sections and the central passage section are connected together to form a single hole.

A burner includes a base and a combustion tray, wherein the base has an inlet pipe and two horn-shaped tubes. The horn-shaped tubes are connected to opposite sides of the inlet pipe, wherein each of the horn-shaped tubes respectively has a first section. A length of the first sections is no less than an inner diameter of the inlet pipe at where the horn-shaped tubes are connected to. The combustion tray is engaged with the base, and communicates with the horn-shaped tubes. Whereby, gas and air could be fully mixed while flowing through each of the first sections. The symmetrical horn-shaped tubes could direct the airflow to the combustion tray, where the airflow could be outputted from flame vents of the combustion tray, whereby to generate more even flame, and to enhance the heating efficiency.

A low NOx burner has a housing that includes a burner head defining a gas manifold and a primary flame zone downstream of the burner head. The burner has a gas inlet for receiving gas. Flow-through air vents are disposed around a center of the burner head and extending through the burner head thereby enabling cold core air to flow from an annular core space upstream of the burner head to the primary flame zone downstream of the burner head. The burner also includes a plurality of premix air vents in fluid communication with the manifold for premixing air and gas within the manifold and for emitting premixed air and gas into the primary flame zone. A plurality of staging pipes extend from the manifold into the primary flame zone for conveying gas into the primary flame zone. The burner includes an ignition device extending into the primary flame zone.

The present inventions provide, among other things, tapered burner tubes having raised gas ports and a smooth interior surface free from obstructions. Venturi members creating a smooth flow of the gas/air mixture along the top of the burner tube are also provided.

Provided is a dual venturi having: a tubular part; a body part, for opening/closing the flow of secondary air by rotating in the horizontal plane and vertical plane directions, the horizontal plane direction being the cross-sectional direction of the tubular part and the vertical plane direction being perpendicular to the horizontal plane; a central passageway, becoming the passageway for primary air; a damper part, and a damper part-side secondary gas outlet; a driving part, for rotationally driving the damper part in the horizontal and vertical planes; a gas inlet-side primary gas outlet connected openly to the damper part-side primary gas outlet; and a gas inlet for introducing gas into the tubular part via the damper part, which openly connects selectively to the damper part-side secondary gas outlet on the basis of the rotational position of the damper part, and for forming the rotational shaft of the damper part along with the rotational shaft of the driving part.

Systems and methods are disclosed that include providing a cooking system that comprises a burner assembly and a heat exchanger, the burner assembly having a high velocity burner configured to provide the necessary high velocity, volumetric flowrate through the heat exchanger having a first fluid circuit having a plurality of compactly-arranged tubes disposed perpendicularly and interstitially to a second fluid circuit having a plurality of compactly-arranged tubes, and the burner assembly also having a low velocity burner configured to significantly reduce and/or substantially eliminate lift off that could result from operation of only the high velocity burner.

An air/gas premix burner is disclosed. The air/gas premix burner includes a fan for sending an air/gas mixture towards a combustion head and a gas valve for regulating the introduction of combustible gas. The air/gas premix burner also includes an air/gas mixer, which comprises a localized pressure loss device, and a combustion head. The air/gas mixer includes two channels. One of the channels is provided with two hinged flaps that are designed to open and close for regulating the flow rate of the mixture.

A gas turbine combustor includes: multiple gaseous fuel nozzles to inject gaseous fuel; a manifold to distribute gaseous fuel to the multiple gaseous fuel nozzles; a burner flange to secure a burner to an end cover; and a burner body to connect the manifold and the burner flange. Gaseous fuel passages are provided in the end cover, the burner flange, and the burner body. The gaseous fuel passage communicates with the manifold. A second manifold is provided in the burner flange. The gaseous fuel passage is provided in the burner body to make the second manifold communicate with the first mentioned manifold.

The present inventions provide, among other things, tapered burner tubes having raised gas ports and a smooth interior surface free from obstructions. Venturi members and air shutters may also be included.