Abstract: An air-fuel burner includes a heat-transfer tube, an air-fuel mixing chamber, and an air-fuel nozzle. The air-fuel nozzle is coupled to the air-fuel chamber to communicate a combustible air-fuel mixture into a combustion chamber defined between the air-fuel nozzle and the heat-transfer tube. The combustible air-fuel mixture, when ignited, establishes a flame in the combustion chamber to produce heat which is transferred through heat-transfer tube to an adjacent medium external to the heat-transfer tube.

Abstract: An air-fuel burner includes a heat-transfer tube, an air-fuel mixing chamber, and an air-fuel nozzle. The air-fuel nozzle is coupled to the air-fuel chamber to communicate a combustible air-fuel mixture into a combustion chamber defined between the air-fuel nozzle and the heat-transfer tube. The combustible air-fuel mixture, when ignited, establishes a flame in the combustion chamber to produce heat which is transferred through heat-transfer tube to an adjacent medium external to the heat-transfer tube.

Abstract: An air-fuel burner includes a heat-transfer tube, an air-fuel mixing chamber, and an air-fuel nozzle. The air-fuel nozzle is coupled to the air-fuel chamber to communicate a combustible air-fuel mixture into a combustion chamber defined between the air-fuel nozzle and the heat-transfer tube. The combustible air-fuel mixture, when ignited, establishes a flame in the combustion chamber to produce heat which is transferred through heat-transfer tube to an adjacent medium external to the heat-transfer tube.

Abstract: A burner assembly includes a fuel nozzle and an air-fuel mixing cone coupled to the fuel nozzle. Fuel is discharged from the fuel nozzle into a mixing chamber formed in the air-fuel mixing cone. Air passes into the mixing chamber through openings formed in the air-fuel mixing chamber and mixes with fuel to form a combustible air-fuel mixture in the air-fuel mixing chamber.

Abstract: A burner assembly includes a fuel nozzle and an air-fuel mixing cone coupled to the fuel nozzle. Fuel is discharged from the fuel nozzle into a mixing chamber formed in the air-fuel mixing cone. Air passes into the mixing chamber through openings formed in the air-fuel mixing chamber and mixes with fuel to form a combustible air-fuel mixture in the air-fuel mixing chamber.

Abstract: A direct gas-fired burner assembly is disclosed in which a two-stage flame is produced. A gas manifold is attached to two baffles with apertures disposed therein. The apertures are designed such that a fuel rich zone occurs near the manifold, while a lean zone occurs away from the manifold. At high fire, the apertures create a negative pressure zone which draws the gas away from the burner thereby allowing a primary flame to burn. The primary flame in the fuel rich zone ignites a secondary flame in the lean zone. Because a flame is burning throughout the entire combustion zone, the flame does not move out past the baffles, the flame remains smaller and cooler, and a lower output of pollutants is achieved.

Abstract: A direct-air, gas-fired air makeup heating unit is disclosed which provides reduced nitrogen dioxide emissions with a higher temperature rise. The unit includes a combustion chamber with a protective chamber downstream of the combustion chamber. At high firing intensity, the flame exits the combustion chamber and enters the protective chamber. The resulting flame is therefore protected from excess air moving around the combustion chamber, thereby lowering nitrogen dioxide emissions even at such high firing intensities.

Abstract: A direct-air, gas-fired air makeup heating unit is disclosed which provides reduced nitrogen dioxide emissions with a higher temperature rise. The unit includes a combustion chamber with a protective chamber downstream of the combustion chamber. At high firing intensity, the flame exits the combustion chamber and enters the protective chamber. The resulting flame is therefore protected from excess air moving around the combustion chamber, thereby lowering nitrogen dioxide emissions even at such high firing intensities.

Abstract: A direct gas-fired burner assembly is disclosed in which a two-stage flame is produced. A gas manifold is attached to two baffles with apertures disposed therein. The apertures are designed such that a fuel rich zone occurs near the manifold, while a lean zone occurs away from the manifold. At high fire, the apertures create a negative pressure zone which draws the gas away from the burner thereby allowing a primary flame to burn. The primary flame in the fuel rich zone ignites a secondary flame in the lean zone. Because a flame is burning throughout the entire combustion zone, the flame does not move out past the baffles, the flame remains smaller and cooler, and a lower output of pollutants is achieved.