The inventive concept relates to a swirler. According to an aspect of the inventive concept, there is provided a swirler including a casing, a pilot body disposed in the casing, and a plurality of vanes arranged along a circumference of the pilot body, wherein at least a part of the vane protrudes further to a downstream than an end portion of the pilot body.

An apparatus and method for producing heat and electricity including a burner to produce radiant heat. A thermal-to-electric conversion device is integrated with the burner and proximate to the radiant heat. The conversion device provides a first side disposed toward the radiant heat and a second side disposed toward a cooling fluid flow path, such as combustion air for the burner or a media to be heated by the burner.

A combustion system includes a fuel and oxidant source, a perforated flame holder, and a support structure that supports the perforated flame holder at a selected distance from the fuel and oxidant source. The fuel and oxidant source outputs fuel and oxidant onto the perforated flame holder. The perforated flame holder receives the fuel and oxidant and sustains a combustion reaction of the fuel and oxidant within the perforated flame holder.