Infrared burner and method of increasing the heat flux radiated therefrom

Claim 1

A method of producing high heat flux in a radiant heat gas burner unit comprising, the steps of providing said burner unit with a ceramic radiant heating plate having plurality of orifices wherein each orifice has an inlet opening connecting into a throat portion of uniform diameter and a tapered outlet portion having a rounded surface extending from said throat portion to a surface of said plate, flowing a combustible air-gas mixture through said orifices at a mass flow rate having a velocity substantially higher than the flame propagation velocity of the mixture such that there is an established central jet of said mixture flowing through each of said orifices, and producing flow separation between said jet and the surface of said outlet portion of each orifice to provide therebetween a zone of turbulent, low velocity recirculating flow in which substantially unrestricted flame propagation occurs.

Claim 2

A method of producing high heat flux in a radiant heat gas burner unit comprising, the steps of providing said burner unit with a ceramic radiant heating plate having plurality of orifices wherein each orifice has an inlet opening connecting into a throat portion of uniform diameter and a tapered outlet portion having a rounded surface extending from said throat portion to a surface of said plate, flowing a combustible air-gas mixture through said orifices at a mass flow rate having a velocity substantially higher than the flame propagation velocity of the mixture such that there is an established central jet of said mixture flowing through each of said orifices, and producing flow separation between said jet and the surface of said outlet portion of each orifice to provide therebetween a zone of turbulent, low velocity recirculating flow in which substantially unrestricted flame propagation occurs.

Claim 3

A method of producing high heat flux in a radiant heat gas burner unit having a radiant heating orifice plate wherein each of the orifices in said plate is defined by a port having a straight throat portion leasing to a tapered combustion portion having a Rounded surface and increasing cross section in the direction of gas flow and which opens at a face of said plate comprising, the steps of producing a relatively high velocity flow of a combustible air-gas mixture in said throat and combustion portions, said flow having a generally uniform cross-sectional area and a velocity greater than the velocity of flame propagation of said mixture, producing a relatively lower velocity recirculation flow of said air-gas mixture in said combustion portion in a zone between said high velocity flow and the surface of said tapered combustion portion, and effecting combustion of said lower velocity flow to heat said surface to incandescence and to ignite said high velocity flow as it leaves said throat portion.

Claim 4

A method of producing high heat flux in a radiant heat gas burner unit having a radiant heating orifice plate wherein each of the orifices in said plate is defined by a port having a straight throat portion leasing to a tapered combustion portion having a Rounded surface and increasing cross section in the direction of gas flow and which opens at a face of said plate comprising, the steps of producing a relatively high velocity flow of a combustible air-gas mixture in said throat and combustion portions, said flow having a generally uniform cross-sectional area and a velocity greater than the velocity of flame propagation of said mixture, producing a relatively lower velocity recirculation flow of said air-gas mixture in said combustion portion in a zone between said high velocity flow and the surface of said tapered combustion portion, and effecting combustion of said lower velocity flow to heat said surface to incandescence and to ignite said high velocity flow as it leaves said throat portion.

Claim 5

A method of obtaining increased radiant heat flux from an infrared gas burner having a plurality of orifices each of which includes a throat portion of relatively small cross section and tapered outlet portion having a rounded surface extending from said throat portion to a surface of said burner and having cross sections that increase progressively in the direction away from said throat portion, comprising passing a combustible gas mixture through said orifices in the direction toward said outlet portions, and establishing a mass flow rate of said mixture through said orifices such that the velocity of flow of the mixture through said throat portion of each orifice is greater than the velocity of flame propagation in said mixture and establishes a substantially laminar flow in said throat portion which projects a jet of said mixture centrally into said outlet portion with separation of said jet from the surface of said outlet portion to create a zone of turbulent, low velocity recirculating flow between said jet and said surface of the outlet portion, and initially igniting said mixture issuing from said orifices, whereupon intense combustion of said mixture occurs in said zone to ignite the mixture issuing from said throat portion in said jet and to effect incandescence of substantially the entire surface of said outlet portion.

Claim 6

A method of obtaining increased radiant heat flux from an infrared gas burner having a plurality of orifices each of which includes a throat portion of relatively small cross section and tapered outlet portion having a rounded surface extending from said throat portion to a surface of said burner and having cross sections that increase progressively in the direction away from said throat portion, comprising passing a combustible gas mixture through said orifices in the direction toward said outlet portions, and establishing a mass flow rate of said mixture through said orifices such that the velocity of flow of the mixture through said throat portion of each orifice is greater than the velocity of flame propagation in said mixture and establishes a substantially laminar flow in said throat portion which projects a jet of said mixture centrally into said outlet portion with separation of said jet from the surface of said outlet portion to create a zone of turbulent, low velocity recirculating flow between said jet and said surface of the outlet portion, and initially igniting said mixture issuing from said orifices, whereupon intense combustion of said mixture occurs in said zone to ignite the mixture issuing from said throat portion in said jet and to effect incandescence of substantially the entire surface of said outlet portion.