A combustion system such as a furnace or boiler includes a perforated reaction holder configured to hold a combustion reaction that produces very low oxides of nitrogen (NOx).

An atomizing burner and corresponding method for turning an atomizing burner from an ON state to an OFF state. The burner has independently controllable flows of atomizing air, combustion air, and fuel flow, the burner in the ON state having flow values of burner parameters including flow of atomizing air, flow of combustion air, and fuel flow. The method includes: changing, in response to an OFF instruction, flow of at least one of the flow of atomizing air, combustion air and/or fuel to a lower non-zero value; first discontinuing, after a first period of time since the changing, flow of fuel and flow of atomizing air; maintaining, for a second period of time since the first period of time, flow of combustion air; second discontinuing, after the maintaining, flow of combustion air; wherein the maintaining prevents buildup of excess heat inside the burner during the transition to the OFF state.

An atomizing burner and corresponding method for turning an atomizing burner from an ON state to an OFF state. The burner has independently controllable flows of atomizing air, combustion air, and fuel flow, the burner in the ON state having flow values of burner parameters including flow of atomizing air, flow of combustion air, and fuel flow. The method includes: changing, in response to an OFF instruction, flow of at least one of the flow of atomizing air, combustion air and/or fuel to a lower non-zero value; first discontinuing, after a first period of time since the changing, flow of fuel and flow of atomizing air; maintaining, for a second period of time since the first period of time, flow of combustion air; second discontinuing, after the maintaining, flow of combustion air; wherein the maintaining prevents buildup of excess heat inside the burner during the transition to the OFF state.

A combustion system supports a swirl-stabilized preheating flame with a preheating fuel and an oxidant. The combustion system preheats a perforated flame holder with the preheating flame. After the perforated flame holder has been preheated to the threshold temperature, the combustion system outputs a primary fuel. The perforated flame holder receives a mixture of the primary fuel and the oxidant supports a combustion reaction of the primary fuel and the oxidant.

There is disclosed an igniter for a gas turbine engine including: a base, a glow plug heater rod, the glow plug heater rod extending from the base along an axis and terminating in a rod end, a sleeve extending circumferentially around the glow plug heater rod along at least a portion of a length of the glow plug heater rod, the sleeve having an inner surface spaced from the glow plug heater rod to provide a gap between the inner surface and the glow plug heater rod, the gap extending radially relative to said axis.

A combustion system such as a furnace or boiler includes a perforated reaction holder configured to hold a combustion reaction that produces very low oxides of nitrogen (NOx).

An atomizing burner and corresponding method for turning an atomizing burner from an ON state to an OFF state. The burner has independently controllable flows of atomizing air, combustion air, and fuel flow, the burner in the ON state having flow values of burner parameters including flow of atomizing air, flow of combustion air, and fuel flow. The method includes: changing, in response to an OFF instruction, flow of at least one of the flow of atomizing air, combustion air and/or fuel to a lower non-zero value; first discontinuing, after a first period of time since the changing, flow of fuel and flow of atomizing air; maintaining, for a second period of time since the first period of time, flow of combustion air; second discontinuing, after the maintaining, flow of combustion air; wherein the maintaining prevents buildup of excess heat inside the burner during the transition to the OFF state.

There is disclosed an igniter for a gas turbine engine including: a base; a glow plug heater rod extending from the base along an axis and terminating in a rod end; and a fuel receiver adjacent the heater rod, the fuel receiver including a portion located closest to the heater rod, the rod end protruding axially relative to the axis from the fuel receiver portion located closest to the heater rod.

There is disclosed an igniter for a gas turbine engine including: a base, a glow plug heater rod, the glow plug heater rod extending from the base along an axis and terminating in a rod end, a sleeve extending circumferentially around the glow plug heater rod along at least a portion of a length of the glow plug heater rod, the sleeve having an inner surface spaced from the glow plug heater rod to provide a gap between the inner surface and the glow plug heater rod, the gap extending radially relative to said axis.

There is disclosed an igniter for a gas turbine engine including: a base; a glow plug heater rod extending from the base along an axis and terminating in a rod end; and a fuel receiver adjacent the heater rod, the fuel receiver including a portion located closest to the heater rod, the rod end protruding axially relative to the axis from the fuel receiver portion located closest to the heater rod.