A burner includes an atomizing chamber, a flame tube in front of the atomizing chamber adapted to direct combusting fuel introduced by the atomizing chamber along an interior of the flame tube, and a controller. The controller is programmed to independently control rate of fuel flow to the atomizing chamber, rate of atomizing air flow to the atomizing chamber, and rate of combustion air to the flame tub. The controller is also programmed to perform operations including regulating, based on output of a gas sensor, at least the rate of combustion air to the flame tube to substantially maintain a first predetermined amount of excess air in the flame tube.

A portable catalytic combustion heater, wherein fuel vapor (11) and air (10) are supplied to a catalyst (6) which promotes the flameless combustion of fuel and releases that. The fuel is supplied as a liquid, passes through a selectively permeable membrane (8) such that fuel vapor exits the membrane and is fed to the catalyst (6). Additional features include porous supports and means of enhancing and diminishing the catalytic rate of combustion and controlling the heat output.

An atomizer includes an endcap having a nozzle; an annular sidewall extending outward from a surface of the endcap and situated radially outward from the nozzle; and a plurality of vanes extending radially inward from the sidewall and axially outward from the endcap, the vanes being set at a non-zero angle of incidence to the sidewall. The annular sidewall and endcap define an fluid chamber between an inlet and the nozzle, and flow from the inlet to the nozzle is at least partially directed through passageways between the vanes, and the flow is imparted with swirling motion from the vanes.

A burner includes an atomizing chamber, a flame tube in front of the atomizing chamber adapted to direct combusting fuel introduced by the atomizing chamber along an interior of the flame tube, and a controller. The controller is programmed to independently control rate of fuel flow to the atomizing chamber, rate of atomizing air flow to the atomizing chamber, and rate of combustion air to the flame tub. The controller is also programmed to perform operations including regulating, based on output of a gas sensor, at least the rate of combustion air to the flame tube to substantially maintain a first predetermined amount of excess air in the flame tube.