Burner construction

Abstract

A burner having a burner body in which combustion air is injected in an air flow pattern which establishes a relatively stagnant air region positioned within the flow of combustion air. A pilot flame injector is positioned to generate a pilot flame extending into the stagnant air region. The pilot flame can, thus, be maintained during the operation of the burner because the stable air conditions within the stagnant air region minimize disruption of the pilot flame by the flow of combustion air. A method for maintaining a uniform pilot flame within a burner operating over a range of combustion air flow rates by introducing combustion air into the burner and providing the combustion air with a flow configuration that establishes a stagnant air zone within the burner that is relatively independent of the flow rate of the combustion air. The pilot flame is then positioned within the stagnant air zone. An injector for feeding finely divided fuel to a burner. The injector includes means to provide an annular passage through which air may flow at high velocity for discharge into a burner. Means are provided to feed fuel into the annular passage such that the fuel may be broken up into minute droplets by the air flow through the passage. Additionally the means to feed fuel are positioned to minimize contact between the fuel and the passage surfaces. Thus, the fuel may be broken up into minute droplets within the air flow stream with the finely divided fuel being discharged into a burner.