The method can include injecting fuel from a liquefied fuel source into a combustion chamber having a combustion path, by circulating the fuel out from an inlet conduit into an evaporator housing, along the evaporator housing in a direction opposite the combustion path and across an evaporator element receiving fuel in the liquid state and exposing a multiplied surface of the liquid fuel to heat from the combustion path to evaporate the liquid fuel, and conveying the evaporated fuel into the combustion chamber and into the combustion path.

A method for a combustion system includes outputting fuel from an adjustable-position fuel nozzle onto a perforated flame holder, the fuel being directed for mixture with an oxidant en route to the perforated flame holder. A combustion reaction of the fuel and the oxidant is supported within the perforated flame holder. A position of the adjustable-position fuel nozzle may be changed relative to the flame holder. A first flow of fuel may be output when the adjustable position fuel nozzle is in an extended state, and a second flow of fuel may be output when the adjustable-position fuel nozzle is in a retracted state.

A liquid-hydrocarbon fuel is used to produce thermal energy by introducing the liquid-hydrocarbon fuel and air to a vaporizer. The liquid-hydrocarbon fuel is vaporized in the vaporizer to produce hydrocarbon-fuel vapor, and the hydrocarbon-fuel vapor and air are blended to form a hydrocarbon-fuel-vapor-and-air mixture. Then, hydrocarbon-fuel-vapor-and-air mixture is introduced to a catalytic combustor including a catalyst, wherein the catalyst promotes oxidation of the hydrocarbon-fuel vapor to form a carbon-dioxide- and water-vapor-containing exhaust and to generate thermal energy. The carbon-dioxide- and water-vapor-containing exhaust and air is then introduced to a recuperator, wherein the recuperator transfers thermal energy from the carbon-dioxide- and water-vapor-containing exhaust to the air to produce heated air.

The method can include injecting fuel from a liquefied fuel source into a combustion chamber having a combustion path, by circulating the fuel out from an inlet conduit into an evaporator housing, along the evaporator housing in a direction opposite the combustion path and across an evaporator element receiving fuel in the liquid state and exposing a multiplied surface of the liquid fuel to heat from the combustion path to evaporate the liquid fuel, and conveying the evaporated fuel into the combustion chamber and into the combustion path.

A miniature liquid combustor includes a double pre-heating structure. A method of operating the combustor comprises introducing liquid hydrocarbon fuel and air into a combustion chamber and stably combusting above a metal catalytic grid. The flames of the combustor first heating a third sleeve, the heated third sleeve gradually radiating the thermal energy to first and second fuel pre-heating chambers until the entire miniature liquid combustor is heated. The process continues to respectively implement second pre-heating of air introduced into the air pre-heating chambers and fuel introduced into the fuel pre-heating chambers before introducing them into the combustion chamber. The resulting combustor and combustion method enable double counter-flow pre-heating of air and fuel before being introduced into the combustion chamber, such that the air and the fuel are fully preheated before combustion.

A fuel-operated vehicle heater, combustion chamber assembly unit includes a combustion chamber housing (14) having a combustion chamber bottom (18) and a combustion chamber circumferential wall (16) extending in a housing longitudinal axis (L) direction to define a combustion chamber (20). A porous evaporator medium (60) is on the combustion chamber circumferential wall or/and the combustion chamber bottom, at an inner side facing the combustion chamber. A fuel feed line (62) feeds liquid fuel into the porous evaporator medium. A first combustion air feed device (68), associated with the combustion chamber bottom, feeds primary combustion air (VP) into a first combustion zone (50) at which the porous evaporator medium is arranged. A second combustion air feed device (70), following the first combustion zone in the housing longitudinal axis direction feeds secondary combustion air (VS) into the combustion chamber at an axially spaced location from the first combustion zone.

A method for a combustion system includes outputting fuel from an adjustable-position fuel nozzle onto a perforated flame holder, the fuel being directed for mixture with an oxidant en route to the perforated flame holder. A combustion reaction of the fuel and the oxidant is supported within the perforated flame holder. A position of the adjustable-position fuel nozzle may be changed relative to the flame holder. A first flow of fuel may be output when the adjustable position fuel nozzle is in an extended state, and a second flow of fuel may be output when the adjustable-position fuel nozzle is in a retracted state.

A combustion system includes a perforated flame holder, an oxidant source, and an adjustable fuel nozzle. The oxidant source outputs oxidant. The adjustable fuel nozzle outputs fuel onto the perforated flame holder. The perforated flame holder supports a combustion reaction of the fuel and oxidant within the perforated flame holder. The position of the adjustable nozzle relative to the perforated flame holder can be adjusted to achieve selected characteristics of the combustion reaction within the perforated flame holder.

The burner includes a first tube portion having a tube end including an ejection port and a second tube portion extending toward the ejection port in the first tube portion. The combustion gas generated by combusting air-fuel mixture is ejected from the ejection port. The second tube portion includes a heat exchanging portion that vaporizes liquid fuel with combustion heat of the combustion chamber and supplies the vaporized fuel to the premixing chamber. The outer surface of the second tube portion functions as a heat receiving surface of the heat exchanging portion. A fuel supply section of the burner is configured to vaporize liquid fuel and supply the vaporized fuel to the premixing chamber, and supply liquid fuel to the heat exchanging portion.

A miniature liquid combustor includes a double pre-heating structure. A method of operating the combustor comprises introducing liquid hydrocarbon fuel and air into a combustion chamber and stably combusting above a metal catalytic grid. The flames of the combustor first heating a third sleeve, the heated third sleeve gradually radiating the thermal energy to first and second fuel pre-heating chambers until the entire miniature liquid combustor is heated. The process continues to respectively implement second pre-heating of air introduced into the air pre-heating chambers and fuel introduced into the fuel pre-heating chambers before introducing them into the combustion chamber. The resulting combustor and combustion method enable double counter-flow pre-heating of air and fuel before being introduced into the combustion chamber, such that the air and the fuel are fully preheated before combustion.