Combuster

Claim 2

Apparatus for utilizing a combustible medium to heat a load fluid, comprising: a conduit; means for pumping a combustible medium through said conduit; means for initially combusting said medium, located along said conduit, for initially combusting said medium while it flows through said conduit; and means for flowing said load fluid against the outside surface of said conduit, along at least conduit locations wherein combustion is occurring, to permit the heating of said load fluid; said conduit having an inside width which can maintain combustion of said combustible medium at a temperature below free flame.

Claim 3

The apparatus described in claim 1 wherein: said conduit has a combustion zone where combustion of said medium occurs, and a preheat zone located up-path from said combustion zone and along which said medium is heated to its combustion temperature, said conduit having sufficiently thick walls between and along at least a portion of each zone, to supply most of the heat to said medium which raises its temperature between 1200° F and its combustion temperature during passage of said medium along said preheat zone.

Claim 4

The apparatus described in claim 1 wherein: said conduit is a tube having a bore width of less than 10 millimeters.

Claim 5

The apparatus described in claim 1 wherein: said conduit is constructed of highly thermally conductive material.

Claim 6

Apparatus for utilizing a combustible medium to heat a load fluid, comprising: inner and outer conduits, said inner conduit lying within said outer conduit; means for moving said combustible medium in a first direction through said inner conduit, and said inner conduit having a region in which combustion occurs; and means for moving a load fluid in a second direction opposite to said first direction, through said outer conduit past said region at which combustion occurs; said inner conduit having an inside diameter which prevents free flame combustion of said combustible medium.

Claim 7

Apparatus for utilizing a combustible medium to heat a load fluid, comprising: inner and outer conduits, said inner conduit lying within said outer conduit; means for moving said combustible medium in a first direction through said inner conduit, and said inner conduit having a region in which combustion occurs; and means for moving a load fluid in a second direction opposite to said first direction, through said outer conduit past said region at which combustion occurs; said inner conduit having an inside diameter which prevents free flame combustion of said combustible medium.

Claim 8

The apparatus described in claim 5 wherein; said inner conduit is of substantially circular shape and has an inside diameter on the order of magnitude of 2 millimeters.

Claim 11

The method described in claim 7 wherein: said step of heating said medium includes conducting heat along walls of said conduit in a direction opposite to the flow direction of said medium therealong, in a quantity that supplies most of the heat which raises the temperature of said medium between 1200° F and the combustion temperature of the medium.

Claim 12

The method described in claim 7 wherein: said conduit has a substantially circular inside of a diameter on the order of two millimeters, and an outside approximately twice the inside diameter; and said combustible medium flows at a velocity on the order of magnitude of 300 centimeters per second along said tube.

Claim 13

Apparatus for utilizing a fuel to heat a load fluid comprising: an inner tube having an inside diameter less than 10 millimeters, and constructed of highly thermally conductive material with its inner and outer surfaces devoid of thermal insulation; an outer tube surrounding said inner tube to leave a space between them; means for mixing said fuel with air to form a combustible medium, and for pumping said combustible medium in a first direction through said inner conduit at a velocity on the order of magnitude of 300 centimeters per second; means for moving said load fluid in a second direction opposite to said first direction through said outer tube; means for initially heating said combustible medium at a predetermined location along said inner tube to a temperature at which it combusts; said inner tube having a wall thickness more than one-fifth the radius of the inside of said tube, whereby to conduct heat in said second direction along the walls of the inner tube to heat the combustible mixture to its combustion temperature.

Claim 14

Apparatus for utilizing a fuel to heat a load fluid comprising: an inner tube having an inside diameter less than 10 millimeters, and constructed of highly thermally conductive material with its inner and outer surfaces devoid of thermal insulation; an outer tube surrounding said inner tube to leave a space between them; means for mixing said fuel with air to form a combustible medium, and for pumping said combustible medium in a first direction through said inner conduit at a velocity on the order of magnitude of 300 centimeters per second; means for moving said load fluid in a second direction opposite to said first direction through said outer tube; means for initially heating said combustible medium at a predetermined location along said inner tube to a temperature at which it combusts; said inner tube having a wall thickness more than one-fifth the radius of the inside of said tube, whereby to conduct heat in said second direction along the walls of the inner tube to heat the combustible mixture to its combustion temperature.