A baffle assembly and burner including the baffle assembly. The baffle assembly includes a collar having a central axis. A plurality of vanes are secured to the collar. Each vane includes a leg extending from the collar at a first angle with respect to the central axis. The first angle of the leg is configured to impart rotation to a flow of fluid through the baffle assembly. An impingement plate extends from the leg at a second angle with respect to the central axis. The second angle is greater than the first angle.

A rich-lean flame burner having on an upper part thereof: a longitudinally elongated lean burner port; and a rich burner port lying adjacent to at least one lateral side of the lean burner port with a clearance therebetween. At a plurality of longitudinal points of straightening members having a plurality of straightening plates which divide the lean burner port into a plurality of laterally sectioned regions, there are disposed first constricted portions which bring upper parts of the straightening plates into intimate contact with each other. Second constricted portions are disposed in at least laterally outermost straightening plates to further divide each portion of the lean burner port that has been divided by the first constricted portions. The second constricted portions are such that the lower end thereof is positioned above the lower end of the first constricted portions, and that the vertical length is shorter than the first constricted portions.

According to the present disclosure, a flat-flame nozzle is provided for producing a flat flame in a flame chamber included in a burner assembly. The flat-flame nozzle is configured to conduct fuel from a fuel supply to an ignition zone in the flame chamber. In some illustrative embodiments, the flat-flame nozzle is also configured to conduct oxygen from an oxygen supply to the ignition zone to produce a combustible oxygen-fuel mixture in the flame chamber. In illustrative embodiments, a removable first plate-separation border frame is positioned to lie between a first lower plate and a companion first upper plate. This border frame is configured to cooperate with those plates to form in the flat-flame nozzle a fuel-discharge outlet and a fuel-transport passageway communicating with the fuel-discharge outlet.

A rich-lean combustion apparatus includes a first plate and a second plate provided to face each other to allow a rich mixture to flow therebetween through a rich mixture passage, a third plate provided to allow a lean mixture to flow through a lean mixture passage formed between the second plate and the third plate, a first burner port member for combusting the rich mixture, and a second burner port member for combusting the lean mixture, wherein, between the first plate and the second plate, a mixture inlet into which some of air supplied from a ventilator and a fuel gas injected from a nozzle are introduced, a mixture passage introduction portion and a mixture passage diffuser for allowing the rich mixture flowed into through the mixture inlet to flow to the rich mixture passage, an air inlet into which the remaining of the air supplied from the ventilator is introduced, and an air passage introduction portion through which the air flowed into through the air inlet flows are formed, and wherein a plurality of air through-holes are formed to pass through the second plate to allow the air of the air passage introduction portion to be spouted into an air passage formed between the second plate and the third plate, and a plurality of distribution holes are formed to pass through the second plate to allow some of a mixture passing the mixture passage diffuser to be spouted into the lean mixture passage.

A water heater is provided that can suppress backflow (entry) of drainage water into a fan from downstream of the fan in a path of a flow of combustion gas. The fan includes a fan case, an impeller housed within the fan case, a drive source attached to the fan case so as to drive the impeller, and a rotation shaft connecting the impeller and the drive source. An exhaust connection portion has a connection portion case and is provided with an exhaust port for emitting combustion gas delivered from the fan to outside of the water heater. The exhaust connection portion also has a drainage water discharge portion for discharging drainage water accumulated downstream of the fan in the path of the flow of combustion gas.

A gas burner membrane is provided. The gas burner membrane comprises a plurality of first layers, each first layer comprises at least one inlet formed therein for receiving a combustible gas mixture, and a plurality of second layers. Successive first layers are separated by a second layer, and at least one outlet is formed between successive first layers.

A combustion system includes a fuel and oxidant source and a flame holder. The flame holder includes a plurality of discrete slats arranged in parallel defining combustion channels between adjacent slats. The fuel and oxidant source outputs fuel and oxidant into the combustion channels. The flame holder holds a combustion reaction of the fuel and oxidant in the combustion channels.

A flame port unit structure of a combustion apparatus provided with a plurality of flame ports for forming a flame comprises: a lean flame port unit, as a flame port for jetting lean gas, including a plurality of lean flame ports arranged along a width direction which is perpendicular to the jetting direction of the lean gas; and a rich flame port unit, as a flame port for jetting rich gas, including a pair of rich flame ports provided on both sides of the lean flame port unit with respect to a width direction, wherein the lean flame port unit comprises a first region in which a gap along the width direction of the lean flame port is formed along a longitudinal direction which is perpendicular to the jetting direction and the width direction, and a second region, provided on both sides along the longitudinal direction of the first region.

A flame port structure for burning a gas includes a first continuous spiral strip, a second continuous spiral strip and a first outflow passage. The first continuous spiral strip has a first side edge, a second side edge and a first plurality of annular segments, and the second continuous spiral strip has a third side edge, a fourth side edge and a second plurality of annular segments, wherein each of the first plurality of annular segments and each of the second plurality of annular segments respectively have two first longitudinal opposite surfaces and two second longitudinal opposite surfaces. The first outflow passage has a first defining wall formed on each of the first respective longitudinal surfaces from the first side edge to the second side edge. The first outflow passage is structured so that the gas produces a specific combustion.

A baffle assembly and burner including the baffle assembly. The baffle assembly includes a collar having a central axis. A plurality of vanes are secured to the collar. Each vane includes a leg extending from the collar at a first angle with respect to the central axis. The first angle of the leg is configured to impart rotation to a flow of fluid through the baffle assembly. An impingement plate extends from the leg at a second angle with respect to the central axis. The second angle is greater than the first angle.