Fluidic burner with heat stability

A burner apparatus, comprising

• (A) a burner body having:
• a central passageway within the burner body having an upstream end and an axially opposed downstream end which opens at a downstream end of the burner, wherein the cross-sectional diameter of the central passageway increases in the direction toward the downstream end;
• a plurality of first ports in the downstream end of the burner which are located substantially evenly around the downstream end of the central passageway, wherein the first ports are connected by first passageways within the body of the burner to one or more inlets through which a first fluid can be fed,
• and a plurality of second ports in the downstream end of the burner which are located substantially evenly around the downstream end of the central passageway, wherein the second ports are connected by second passageways within the body of the burner to one or more inlets through which a second fluid can be fed, the first and second passageways being separate from each other;
• wherein the first ports and the second ports are substantially uniformly distant from the central axis of the central passageway;
• wherein the plurality of first ports and the plurality of second ports are located in the inner surface of the central passageway upstream from the downstream end of the central passageway;
• and wherein the central passageway, the first ports, and the second ports, are the only openings in the burner apparatus through which fluid can flow out of the downstream end of the burner apparatus;
• (B) a fluidic cavity communicating at the downstream end thereof with the upstream end of the central passageway of the burner, said fluidic cavity having a diameter D at said point of communication sufficient to enable fluid passing therethrough to have a supersonic velocity, said central passageway having a length from said point of communication to its downstream end of from 2D to 9D;
• (C) a plurality of biasing gas passageways through which biasing gas can be fed into the fluidic cavity in a direction substantially perpendicular to the axial centerline of the fluidic cavity, said passageways having a diameter d such that d/D is within the range of from 0.18 to 0.75, said passageways communicating with the fluidic cavity at a point within the range of from 3d/4 upstream to d/4 downstream of the point of communication between the fluidic cavity and the upstream end of the central passageway, where D and d are expressed in the same units;
• and (D) a housing which surrounds the downstream end of the burner and which is open at the end of the housing that surrounds the downstream end of the burner, wherein the open end of the housing is located a distance L downstream from the downstream end of the burner, wherein L is at least 25% of the distance across the open end of the housing, wherein the portion of the housing that extends downstream of the downstream end of the burner comprises passageways therein through which coolant can flow to absorb heat generated by combustion occurring at the burner.