Gas burner

State of the art

0001The invention relates to a gas burner with a burner body of a porous structure is at least partially penetrated, and in which a Fuel gas-air mixture is combustible, and a method for combustion a fuel gas-air mixture in a gas burner.

0002In such gas burners is the porous burner body, such as a Ceramic foam, a bed of solids or a wire mesh on a Distribution plate fitted. He may have a cylindrical, cubic or as Example have rectangular shape. The burner body, the fuel gas-air mixture supplied via the distributor plate.

0003At low burner power of the reaction zone extends from the Manifold plate only slightly into the torch body. With increasing burner output spreads the combustion zone in the flow direction, increasingly in the body of the burner. In the interpretation of the torch body whose volume is dimensioned so that, at maximum burner capacity almost the entire burner body held combustion processes. at low burner performance decreases due to heat Auskopplungs operations the temperature in the reaction zone transversely to Srömungsrichtung. Due to the prevailing in the edge areas of low temperatures CO can not be CO₂ react. This creates an undesirable high CO production.

0004It is an object of the invention to a gas burner of the type mentioned create, or a combustion method to put to disposal, in which a low CO production can be realized.

0005This object is achieved by the fact that the transverse to the flow direction of the combustion gas-air mixture extending cross-sectional area of ​​the reaction zone of the torch body, in which the combustion takes place in the flow direction increases at least in a partial area of ​​the burner body. At a The method according to the invention it is provided that at low a Burner output of the gas burner has a higher temperature-volume load in Burner body is generated than at a higher burner capacity.

0006The design according to the invention of a gas burner allows for less Burner output increased temperature surfaces, or -Volumenbelastung. This can also be in this mode, a temperature level in realize torch body, wherein the CO to CO₂ can react. In such Gas burners is also a higher modulation range for the burner output realizable than with conventional gas burners. It may here already at low fuel gas-air mixture concentrations controlled incineration done.

0007With a gas burner according to the invention it can be provided that the Cross-sectional area of ​​the reaction zone continuously increased. This let itself realize, for example, by such a design variant in which the burner body has a truncated cone-shaped geometry, wherein the inlet cross-sectional area on the torch body, the fuel gas-air mixture flows in, is formed by the smaller circular surface of the torch body. The measure the taper of the burner body is in this case by the desired modulation range the gas burner determined.

0008Conceivable but it is also that the combustion gas-air mixture in the torch body introduced via a feed line and here on a cylindrical or spherical Distribution is delivered. The fuel gas-air mixture can ring or spherical flow into the torch body and ignite here. dependent of the burner output fills the reaction zone to the torch body or more less out.

0009It may also be provided, the cross-sectional area of ​​the reaction zone increases via one or more step jumps. Here, then certain Service areas associated with the various increments. For example the use of three increments has proven to give a first increment covers 0 to 40% of the burner capacity, a second 40 to 60% and the third increment from 60 to 100% of the burner capacity.

0010For manufacturing simplicity, it may be provided that the burner body two or more cylindrical or disc-shaped part-burning body having having a different diameter, and in that the Central longitudinal axes of the partial internal bodies are arranged flush with one another.

0011In order to determine certain performance areas, there may be provided, that the partial internal body in the flow direction of the combustion gas-air mixture having different thicknesses. It is also conceivable that a torch body such a cross-sectional geometry in the reaction zone extending partially continuously and partially via one or more increments enlarged.

0012The invention will in the following with reference to illustrated in the drawings Embodiments explained in more detail. Show it:<dl tsize="7"><dt>Fig. 1</dt><dd>in a schematic side view of a torch body with truncated cone-shaped geometry,</dd><dt>FIG. 2</dt><dd>in a schematic side view of a torch body with partially truncated conical and partially cylindrical Geometry,</dd><dt>Fig. 3</dt><dd>in a schematic side view of a burner body consisting of three partial internal bodies composed,</dd><dt>Fig.4</dt><dd>in a schematic side view of another burner body which is composed of three sub-internal bodies and</dd><dt>Fig. 5</dt><dd>a disc-shaped in a perspective diagram Torch body with a lead.</dd></dl>

0013In FIG. 1, a burner body 10 is shown having a stumpfkelgeförmige having geometry. The torch body 10 is of a lateral jacket face 13, an input surface 11 and an exhaust gas outlet surface 12 limited. The Entrance surface 11 and the exhaust gas outlet surface 12 are circular. The burner body 10, a fuel gas-air mixture through the inlet surface 11 fed. It flows into the porous burner body 10 and ignited themselves. For small burner capacities extends the reaction zone in which the Fuel gas-air mixture is reacted, starting from the entrance surface 11 only low in the torch body 10 inside. Due to the conical geometry of the Torch body 10, the available combustion volume at the low Burner output low. This results in a high-temperature areas and - volume overload. With increasing burner output is also the volumetric flow of fuel gas-air mixture which flows into the burner body 10 elevated. The reaction zone extends increasingly into the torch body 10 in. This also increases the reaction zone. The Temperature surfaces or - volume load then decreases.

0014In FIG. 2, a torch body 10 is illustrated, the two partial internal body 14.1, 14.2 has. The partial combustion body 14.1 has a frustoconical Geometry. The partial internal body 14.2 is cylindrical. The two Partial focal body 14.1, 14.2 can be made individually or it may be provided that these are integrally connected to each other. In the part-burning body 14.1 is a continuous increase in the Queschnittsfläche the Brennerkörpes 10 realized. Here can be a certain power range the gas burner exit. For example, the performance here of 0 to 40% of the total power of the gas burner, respectively. Following the Partial burning body 14.1 shifts the reaction zone via the entrance face 11 '' in the second part-internal body 14.2. In this area, the remaining Power of the gas burner be extended.

0015Fig. 3 illustrates a gas burner 10, in which the cross-sectional area increases in the flow direction of the gas-air mixture over increments. For this three-part internal body 14.1, 14.2, 14.3 are used. This part-burning body 14.1, 14.2, 14.3 have a cylindrical shape and are of the Coat surfaces 13 limited. The central longitudinal axes of the partial combustion body 14.1, 14.2, 14.3 are arranged in alignment to each other. The extent of the partial burning body 14.1, 14.2, 14.3 in the direction of flow is the same in each case. Each Sub-burning body 14.1, 14.2, 14.3 is a specific power range of Gas burner assigned. In a medium power range used for example the partial combustion body 14.1 and partly also the partial burning body 14.2 as reaction zone.

0016Fig. Figure 4 illustrates an alternative embodiment to the burner body 10 FIG. 3. Here, the cylindrical part-burning body 14.1, 14.2, 14.3 different extents in the direction of flow of the gas-air mixture on. To the lower power range of the gas burner increased to achieve variability of the temperature-volume load, are the two part-burning body 14.1, 14.2 formed narrow.

0017In FIG. 5, a burner body 10 having a cylindrical shape. In the Torch body 10 may be via a feed pipe 15 and a distributor 16 Fuel gas-air mixture are introduced. This flows from the manifold 16 in the porous burner body 10 and ignited here. The fuel gas-air mixture escapes the manifold and flows into the torch body 10th at low burner capacities is the reaction zone close to the manifold 16 arranged around. At higher burner capacities, the reaction zone extends also annular increasingly into the torch body 10th The resulting from the combustion gases are dispersed over the surface 13, which serves as exhaust gas exit surface 12th