Method and apparatus for controlling gas flow patterns inside a heater chamber and equalizing radiant heat flux to a double fired coil

A method for operating a heater enclosure, the method comprising:

• providing a combustion chamber having a pair of opposing sidewalls, a pair of opposing end walls, and a top wall opposing a bottom wall, each wall being substantially planar and positioned to collectively define a cavity therein;
• inducing a fluid flow within the cavity and adjacently along at least one of the walls in a single direction, the fluid flow comprising a fuel component, an air component, and a combustion product component, and
• providing at least one structure on the wall that is adjacent to the fluid flow, the structures creating a beneficial pressure gradient that maintains the fluid flow adjacently against the wall, and wherein the fluid flow is maintained substantially adjacent along the internal surface of one or more walls during operation of the heater enclosure,
• wherein the structure comprises at least one dimple, and
• wherein the surface of one or more dimples is entirely formed with a constant radius.

A heater enclosure, comprising:

• a pair of opposing sidewalls, each sidewall having a substantially planar internal surface;
• a pair of opposing end walls, each opposing end wall being substantially perpendicular to each opposing sidewall and having a substantially planar internal surface;
• an opposing top wall and bottom wall, the top wall being substantially perpendicular to each opposing sidewall and to each opposing end wall and having a substantially planar internal surface, the bottom wall being substantially perpendicular to each opposing sidewall and to each opposing end wall and having a substantially planar internal surface, wherein the internal surfaces of each wall collectively form a cavity therein;
• one or more nozzles coupled to one or more walls, the nozzles introducing a fluid flow into the cavity and adjacently along the internal surface of at least one of the walls, the fluid flow undergoing combustion thereby producing heat;
• and
• one or more dimples extending inwardly from the internal surface of the wall that is adjacent to the fluid flow, the dimples maintaining the fluid flow substantially adjacent along the internal surface of the wall that is adjacent to the fluid flow,
• wherein the depth of one or more dimples is entirely formed with a constant radius, the dimples directing the heat radiantly towards a plurality of tubes and reducing peak radiant flux rates exposed on the plurality of tubes, the plurality of tubes passing through at least a portion of the cavity.

A heater enclosure, comprising:

• a pair of opposing sidewalls, each sidewall having a substantially planar internal surface;
• a pair of opposing end walls, each opposing end wall being substantially perpendicular to each opposing sidewall and having a substantially planar internal surface;
• an opposing top wall and bottom wall, the top wall being substantially perpendicular to each opposing sidewall and to each opposing end wall and having a substantially planar internal surface, the bottom wall being substantially perpendicular to each opposing sidewall and to each opposing end wall and having a substantially planar internal surface, wherein the internal surfaces of each wall collectively form a cavity therein;
• one or more air supply nozzles coupled to one or more walls, the air supply nozzles introducing an air flow into the cavity and adjacently along the internal surface of at least one of the walls;
• one or more fuel supply nozzles coupled to one or more walls, the fuel supply nozzles introducing a gas flow into the cavity and adjacently along the internal surface of the same wall that the air flow is introduced, the gas flow and the air flow being combined within the cavity to form at least a portion of a fluid flow;
• and
• one or more structures extending inwardly from the internal surface of the wall that is adjacent to the fluid flow, the structures maintaining the fluid flow substantially adjacent along the internal surface of the wall that is adjacent to the fluid flow,
• wherein the fluid flow undergoes flameless combustion, thereby generating heat,
• wherein the structure comprises at least one dimple, and
• wherein the depth of one or more dimples is entirely formed with a uniform radius.