EP0494631B1 - Portable burner for fuel gas with two mixing tubes - Google Patents

Description

The invention relates to a portable burner with a first injector nozzle for fuel gas, which is arranged in the region of a first suction point for primary air at the inlet end of a first mixing tube, with a swirl generator, which is at a distance in front of the outlet end of the first mixing tube forming a second nozzle with a nozzle axis this is arranged, and with a second mixing tube, the inner cross-section (F2) of which is larger than the inner cross-section (F1) of the first mixing tube and which is arranged concentrically with the outlet end of the first mixing tube directly generating a burner flame, an inlet end for the burner flame and second suction points for Has secondary air in the region of the outlet end of the first mixing tube and extends in the flow direction to its outlet end.

The fuel gas is usually obtained by vaporizing liquefied petroleum gas such as propane, butane or mixtures thereof and their pressure-controlled delivery.

It is known that a gas jet, when entering a gaseous medium which is initially stationary, sets it in motion, to a certain extent entrains it and conveys it in the same direction. This process, also known as the injector process, is based on friction, turbulence and diffusion processes. It also takes place in an open atmosphere. However, the efficiency can be increased by having these processes run in a tubular housing which is composed of nozzles, line sections, inlet and outlet openings. Known examples of use are the jet suction device or the jet pump, including the diffusion pump, and the gas burner, including the Bunsen burner familiar from school lessons.

The initial impulse of the gas jet, which is usually generated by a nozzle (conversion of pressure into speed), is distributed over the entrained gas. If there is a lack of guidance, the cross section of the gas jet quickly becomes larger and slower until the energy is used up by friction and / or - after deducting the losses - has been converted back into pressure.

Nevertheless, a gas jet in initially still air has a very considerable range, which can be seen from examples of everyday life: You can, however, make a candle flicker by breathing air from two meters away - if not blow it out. When a jet plane takes off, the jet extends into the landscape for miles, so that subsequent starts have to be postponed until the atmosphere calms down.

Media of different densities and / or temperatures are particularly difficult to mix. A "temperature stratification" occurs over long distances.

From DE-OS 22 54 891 gas burners of the type described at the outset are known which are provided for shrinking or welding plastic films and which consequently have to generate hot gas with low outlet temperatures. In the disclosed exemplary embodiments, the second mixing tube is either (A) in its entire length without openings, or (B) the openings extend to the outlet end or in any case in the immediate vicinity of the outlet end of the second mixing tube. As a result, the secondary air flows in essentially in the axial direction, which will be explained in more detail below.

In case (A), the second mixing tube is widened at the inlet end and forms an inlet cone or a type of spatial elbow with the adjacent walls of the combustion chamber, which deflects the cold air drawn in near the wall of the mixing tube in a purely axial direction before the cold air reached the burner flame. Temperature compensation can only be achieved through the divergence of the flame beam and edge turbulence. However, since the outlet opening of the combustion chamber is oval or slit-shaped, this can only be done in one plane. A temperature stratification is maintained at least over a considerable length of the second mixing tube, so that a temperature profile with a maximum in the middle is generated at the outlet opening of the second mixing tube: the hot core of the gas jet extends correspondingly far.

Also in case (B) the second mixing tube is completely open at the inlet end. Due to the even distribution of the perforations over the whole or most of the length of the mixing tube, this has practically no effect: The hot gas jet acts like a free jet, which is also expressly pointed out. As a result, suction takes place essentially in the axial direction: cold air and Hot gas flow essentially parallel to each other, and there is a far-reaching gas jet with a hot core, ie with a temperature stratification, which is only gradually reduced, ie with increasing distance from the combustion chamber, by jet divergence and mixing.

All burners have in common that due to limited dimensions, unavoidable internals such as flame holders, subdivided suction channels etc. in the flow and in the flame, different mixing ratios of fuel gas and air and thus additionally locally limited zones of different temperatures are formed, which are also clearly as in the flame light and dark streaks or "streaks" can be seen.

Insofar as swirl generators are used in the known solutions for generating a swirl flow, this increases the temperature stratification, which cannot be canceled again by the oval or slot-shaped end of the combustion chamber. This is discussed in more detail below:

From US Pat. No. 4,013,395 it is known to delimit a combustion chamber from the single mixing tube by means of a swirl generator serving as a flame holder in the form of radial guide vanes. The swirl generator sets the initially still cold mixture of fuel gas and ambient air in a rapid rotation, which continues in the combustion chamber around its axis. The resulting centrifugal forces cause the relatively colder gas flows (with high density) to be thrown against the wall of the combustion chamber and cool them, while the relatively hot gas flows (with lower density) collect in a core zone. This core zone is the actual, very hot, working flame, the very one protrudes far from the mouth of the burner. This known burner does not have a second mixing tube. Such a torch is preferably used for welding and brazing metals.

DE-OS 22 54 891 and US-PS 4 013 395 pursue diametrically opposite paths and goals.

EP-OS 0 240 751 discloses a low-pressure hand burner in which a hot flame core is separated from the combustion chamber wall by a jacket flow of cool ambient air without a swirl generator. Here too, a hot, far-reaching flame is generated, which emerges from the combustion chamber. The sheath flow cooling the combustion chamber wall is achieved by sucking in the ambient air through the rear of the burner, in which there are openings which produce an air flow parallel to and in the immediate vicinity of the combustion chamber wall. This parallel flow is wanted and complicates a mixing process.

From GB-PS 304 938 a non-generic burner with two series-connected injection systems for the suction of primary and secondary air is known, which is to be screwed stationary with a fixed line with the vertical alignment of all nozzles. It should be achieved by several adjusting devices and the design specification for the flow channels that the respective gas-air mixture completely fills the cross-section of the flow channel arranged downstream of each nozzle and that such a flow speed with graded stoichiometric mixing ratios is achieved that the burner flame does not strike back into the flow channels . According to regulations, no flame burns in the last, cold injection tube. Rather, a far-reaching hot flame emerges from the last mouth. A turbulence of the gases within the burner should even be explicitly avoided.

The invention is therefore based on the object of improving a burner of the type specified in such a way that it produces a hot gas stream of relatively low temperature and with a temperature distribution which is as uniform as possible when the length of the second mixing tube is limited. In particular, no visible flame should emerge from the outlet opening of the second mixing tube in order to use the burner to temperature-sensitive materials such as roofing felt, roofing foils and the like, even when operated improperly. to be able to process.

• a) zwischen dem Austrittsende des ersten Mischrohres und dem Eintrittsende des zweiten Mischrohres ein den radialen Abstand zwischen beiden Rohrenden zumindest im wesentlichen ausfüllender Füllkörper mit einer sich im wesentlichen radial zur Düsenachse (A-A) erstreckenden Stirnfläche angeordnet ist, aus der das die zweite Düse bildende Austrittsende des ersten Mischrohres um ein vorgegebenes Maß "s" herausragt, und daß
• b) die zweiten Ansaugstellen für die Sekundärluft ausschließlich im Bereich des Austrittsendes des ersten Mischrohres angeordnet und radial auf die Düsenachse ausgerichtet sind, derart, daß die Sekundärluft im wesentlichen senkrecht bzw. radial auf die Anfangsstrecke der in Richtung der Düsenachse verlaufenden Brennerflamme auftrifft, und daß das zweite Mischrohr zwischen den zweiten Ansaugstellen und seinem Austrittsende einen geschlossenen Mantelteil aufweist, dessen Länge mindestens das Dreifache der axialen Ausdehnung der zweiten Ansaugstellen besitzt.

The problem is solved in the burner described above according to the present invention in that

• a) between the outlet end of the first mixing tube and the inlet end of the second mixing tube a filling body is arranged which at least substantially fills the radial distance between the two tube ends and has an end face which extends essentially radially to the nozzle axis (AA) and from which the outlet end forming the second nozzle of the first mixing tube protrudes by a predetermined amount "s", and that
• b) the second suction points for the secondary air are arranged exclusively in the region of the outlet end of the first mixing tube and are aligned radially with respect to the nozzle axis, such that the secondary air impinges essentially perpendicularly or radially on the initial path of the burner flame running in the direction of the nozzle axis, and that the second mixing tube between the second suction points and its outlet end has a closed jacket part, the length of which has at least three times the axial extent of the second suction points.

The feature a) prevents or suppresses the formation of an axially parallel flow of the secondary air from the start.

Characteristic b) ensures that the sucked-in secondary air hits the starting section of the burner flame at a right angle and favors its swirling and mixing with the secondary air at a very early point in time. The secondary air drawn in transversely thus serves, as it were, to break up any cool edge or jacket flow that would be expected due to the swirl generator and to prevent it from forming again. The transversely entering secondary air not only slows down the swirl and centrifugal effect, which is desirable in the end of the first mixing tube, but also the formation of an excessive axial speed in the area of the jet axis. The result is great uniformity in the diametrical temperature profile at the outlet end of the second mixing tube. Since a large amount of secondary air is drawn in, the average temperature of the hot gas is relatively low; it is between about 500 and 650 ° C. Above all, no flame emerges from the burner, so that temperature-sensitive materials such as roofing felt and roof foils can be processed even by inexperienced people. The burner's inherent safety is due to the warranty obligation e.g. a roofing company of crucial importance.

It is important that the design of the first injector system is such that a largely stoichiometric gas mixture is generated which already allows complete combustion. The addition of large amounts of secondary air does not serve to continue the combustion process, but to lower the temperature while increasing the mean flow rate, since the heat transfer is improved with the flow rate.

The relative shortness of the second mixing tube makes production cheaper and easier to use. The absence of any openings in the area beyond the second suction points favors the mixing process over the entire cross section of the second mixing tube. Nor can it occur that energy losses occur due to the spreading of the hot gas flow and mixing with air volumes lying apart, as is the case in the prior art with such second mixing tubes which are large over their entire length or at least most of their length Openings are provided so that practically a free jet is formed. This in turn leads to temperature stratification.

A particularly simple burner design is obtained if the filler body is designed as a rotationally symmetrical part with an inner bore for inserting the first mixing tube and with at least one outer surface for attaching the second mixing tube. In this case, the packing is the only and also simply designed and rigid coupling part between the two mixing tubes.

You can also use this to demonstrate the different effects of only axial and radial suction of the secondary air in an impressive way: The filling body is provided with axial suction openings for secondary air. If you now close the radial suction openings in the second mixing tube, the flame emerges from the second mixing tube in the form of a hot core. In this case, the burner can also be lit at the outlet opening of the second mixing tube, which also demonstrates the insufficient gas mixture. With the radial inflow according to the invention, this does not succeed because the ignition limit of the gas mixture is clearly undershot at all points. In this case you have to use the burner ignite through the radial suction openings.

It is furthermore particularly advantageous if the outlet end of the first mixing tube forming the nozzle protrudes from the end face of the filling body by 4 to 15 mm, preferably by 6 to 12 mm. A practically proven value is 9 mm. This nozzle projection allows a sufficient overlap of the nozzle edge with the transverse flow generated by the slots and explained in more detail below.

The nozzle at the end of the first mixing tube is, so to speak, the injector nozzle for the second mixing tube. Their effect is not necessarily dependent on the nozzle being formed by narrowing the first mixing tube; the increase in gas velocity through the combustion process is already sufficient to produce an intake effect. However, it is advantageous to increase the effect of the nozzle by restricting the flow, namely in that the circular end edge of the outlet end of the first mixing tube is rounded inwards on the entire circumference to such an extent that the outlet diameter is 15 to 25%, preferably around 19 to 21%, compared to the inner diameter of the first mixing tube is reduced.

To achieve a good mixing effect of fuel gas and primary air, it is particularly advantageous if the ratio of the distance (d) from the end face of the swirl generator to the end edge of the outlet end of the first mixing tube to the inside diameter (D1) of the first mixing tube is at least 1.0, preferably 1.1 to 1.5.

It has also proven to be advantageous if the swirl generator has guide vanes which are distributed around the axis (AA) of the first mixing tube and whose angle of attack with respect to the axis (AA) on the outer diameter of the swirl generator is less than 40 degrees, preferably less than 35 degrees. It has been shown that the angle of attack should be selected to be smaller with increasing burner output given the dimensions of the mixing tubes. It is also advantageous if the swirl generator is chamfered significantly on the inlet side and if the angle of the surface lines of the bevel with respect to a radial plane at least largely corresponds to the angle of attack of the guide vanes with respect to the axis AA.

Particularly optimal burning properties are achieved when the ratio of the inner cross section (F2) of the second mixing tube to the inner cross section (F1) of the first mixing tube is between 4.0 and 4.8, preferably about 4.3.

In a preferred embodiment of the burner, the second suction points are designed as axially parallel slots distributed over the circumference of the second mixing tube, the end portions of which are oriented towards the filler body or the nozzle at least partially overlap with the partial section of the first mixer tube protruding from the end face of the filler body.

The proportion of all slots, as seen in the circumferential direction, should be at least 50 percent of the total circumference of the second mixing tube. An upper limit is only given by the strength limits of the material of the second mixing tube, since the slots naturally weaken the material.

Furthermore, the ratio of the sum of the cross-sectional areas of all the slots to the inner cross section of the second mixing tube should be at least 1.2 and should preferably be between 1.4 and 1.5.

It is also expedient if the ratio of the length of each individual slot to the length of the second mixing tube projecting beyond the packing is between 0.10 and 0.20, preferably between 0.14 and 0.17. This ensures a sufficiently large closed length of the second mixing tube.

For simultaneous processing of large areas, it is also advantageous if the burner is attached to a cross member with several identical burners with their axes (A-A) aligned parallel to one another and forming a burner battery and connected to a common gas supply line running parallel to the cross member.

In order to ensure a burner movement at a constant distance over the surface to be processed, it is advantageous if the burner battery is provided with castors, whose horizontal axes of rotation are perpendicular to the burner axes (A-A).

In order to concentrate the hot gases on the given processing area and to reduce the disruptive influence of cross winds, especially outdoors, it is also advantageous if baffle plates are arranged on both sides of the burner battery, the vertical main planes of which run parallel to the burner axes.

Further advantageous embodiments of the subject matter of the invention result from combinations of features from the subclaims with one another and with those of the main claim and from the following detailed description.

Exemplary embodiments of the subject matter of the invention are explained in more detail below with reference to FIGS. 1 to 6.

Figur 1

einen Axialschnitt durch den Brenner,

Figur 2

eine Draufsicht in axialer Richtung auf die ebene Stirnfläche des Drallerzeugers innerhalb des ersten Mischrohres in vergrößertem Maßstab,

Figur 3

eine Seitenansicht senkrecht zur Achse des Drallerzeugers nach Figur 2

Figur 4

einen Brenner nach Figur 1, der durch einen Handgriff zu einem Handbrenner ausgestaltet ist,

Figur 5

eine Vereinigung mehrerer Brenner nach Figur 1 zu einer fahrbaren Brennerbatterie in betriebsbereitem Zustand, und

Figur 6

eine Brennerbatterie nach Figur 3 mit nach oben und hinten geschwenkten Leitblechen.

Show it:

Figure 1

an axial section through the burner,

Figure 2

3 shows a plan view in the axial direction of the flat end face of the swirl generator within the first mixing tube on an enlarged scale,

Figure 3

3 shows a side view perpendicular to the axis of the swirl generator according to FIG. 2

Figure 4

a burner according to Figure 1, which is designed by a handle to a hand torch,

Figure 5

a combination of several burners according to Figure 1 to a mobile burner battery in an operational state, and

Figure 6

a burner battery according to Figure 3 with baffles pivoted up and back.

1 shows a basic element of a portable burner 1 with a first injector nozzle 2, to which the fuel gas is fed via a line 3 from a liquid gas container, not shown. The injector nozzle 2 is arranged in the region of a first suction point 4 for primary air at the inlet end 5 of a first mixing tube 6. The suction point 4 consists of four radial bores 7 distributed over the circumference. An insert 8, which forms a Venturi tube, is located in the first mixing tube immediately following the bores 7. The insert 8 is followed by a mixing section 9 which merges into a swirl generator 10 which consists of a hub with radially projecting guide vanes 11. The guide vanes can also be formed by material sections between oblique bores in a cylindrical body.

The angle of attack of the guide vanes 11 on the outer diameter of the swirl generator 10 or the axes of the bores with respect to the axis (A-A) is 30 degrees. The swirl generator 10 has an end face 12 which is arranged at a distance "d" of 32 mm in front of the outlet end 13 of the first mixing tube 6 which forms a second nozzle with a nozzle axis. The inner diameter "D1" of the first mixing tube is 26 mm, so that the ratio of d: D1 = 1.23.

As can be seen more clearly from FIGS. 2 and 3, the swirl generator 10 has five guide vanes 11 and five intermediate channels 11a with an angle of attack of 30 degrees. On the entry side opposite the end face 12, the swirl generator is tapered in order to form a chamfer, and at the same angle of 30 degrees, but with respect to a radial plane to the axis A-A. This favors the flow and more air / fuel gas mixture can be passed through to increase performance. The diameter of the smallest circumferential edge on the chamfer is approximately the core diameter of the swirl generator 10.

The circular end edge 14 of the outlet end 13 of the first mixing tube 6 is rounded inward so far that the free diameter "Dd" of the nozzle is 21 mm, i.e. the diameter is reduced by 19.23%, the cross section by 34.76%; the exit speed is increased accordingly.

The downstream end of the first mixing tube 6 is inserted into an inner bore 15 of a filler body 16, which is designed as a rotationally symmetrical part and has at least one outer surface 17 for fitting a second mixing tube 18. This second mixing tube is also cylindrical, has an over the end face 21 of the packing 16 protrudes length L = 295 mm, and its inner cross section "F2" is 54 mm in diameter larger than the inner cross section "F1" of the first mixing tube 6, namely 2,289 mm²: 530 mm². The ratio of the internal cross section (F2) of the second mixing tube 18 to the internal cross section (F1) of the first mixing tube 6 is therefore approximately 4.31. The second mixing tube 18 is arranged concentrically to the outlet end 13 of the first mixing tube 6 and has an inlet end 19 for the burner flame and second suction points 20 for secondary air.

The radial distance between the outlet end 13 of the first mixing tube 6 and the inlet end 19 of the second mixing tube is closed by the filler body 16. The end face 21 of the filling body extends essentially radially to the nozzle axis (A-A), and the outlet end 13 of the first mixing tube 6, which forms the second nozzle, projects from it by a predetermined dimension "s", which in the present case is 9 mm.

The second suction points 20 for the secondary air are arranged exclusively in the area of the outlet end 13 of the first mixing tube 6 and are radially aligned with the nozzle axis A-A. As a result, the secondary air is directed essentially perpendicularly to the initial section of the burner flame running in the direction of the nozzle axis.

Between the second suction points 20 and its outlet end 23, the second mixing tube 18 has a closed jacket part 18a, the length of which is 5.17 times the axial extent of the second suction points 20. Particular attention should be paid to the location and dimensions of these second suction points:

The second suction points 20 are distributed axially parallel to the circumference of the second mixing tube 18 Slots 24 formed. There are 7 slots with a width of 13 mm, which are rounded in a semicircle at both ends. The length "LS" is 47 mm, so that an entry cross section of 475 mm² per slot or a total cross section of 3,325 mm² is calculated. The ratio of this total cross section to the inside cross section of the second mixing tube is 1.45.

The end sections 24a of the slots 24 aligned with the filler body 16 overlap by about 7 to 8 mm with the section of the first mixing tube 16 which protrudes from the end face 21 of the filler body 16. The length of the slots also ensures that the secondary air has a considerable amount of air Part of the initial section of the flame, not shown, strikes and forces it to swirl.

The width of the axially parallel webs 25 between the slots is 11 mm, so that the proportion of all slots 24, viewed in the circumferential direction, is 18 = 13: (11 + 13) or 54.1 percent of the total circumference of the second mixing tube.

Figure 1 shows the basic building block for various stages of the burner according to the invention. FIG. 4 shows that a hand torch can be formed from this by attaching a handle 26 with a connecting thread 27 for a gas hose to the filling body 16.

In a connecting piece 28 between the handle 27 and the filler 16 there is a gas valve 29 with an adjustment button 29a. The connecting piece 28 is connected beyond the gas valve 29 to the injector nozzle 2 via a gas line 30. The hand torch can be supplemented by a piezo igniter, one ignition electrode of which is located in front of the end edge 14 of the first mixing tube (not shown).

Figures 5 and 6 show a burner battery 31 for simultaneous heating of large areas. The burner battery is formed in that a burner 1a according to FIG. 1 with several similar burners 1b, 1c, 1d,... Is attached to a cross member 32 with their axes (AA) parallel to one another and to a common gas supply line running parallel to the cross member 33 are connected.

Furthermore, a guide rod 34 with a handle 35 is attached to the cross member 32, and a feed line 36 with a gas valve 37 is attached to the guide rod, which is connected to a gas hose 38, which leads to a liquid gas container, not shown, with a pressure regulator.

In order to be able to guide such a burner battery by a walking person at a constant distance over a processing surface, the burner battery 31 is provided with castors 39, only one of which is shown and whose horizontal axes of rotation are perpendicular to the burner axes.

To concentrate the heat and largely eliminate the disturbing influence of cross winds 31 baffles 40 and 41 are arranged on both sides of the burner battery, the vertical main planes of which run parallel to the burner axes. The lower edges 42 of the guide plates are located just above the processing area. As can be seen from Figure 4, the baffles are pivotally attached upwards and backwards.

Claims (17)

1. Portable burner (1), comprising a first injector nozzle (2) for fuel gas arranged in the area of a first suction point (4) for primary air at the inlet end (5) of a first mixing tube (6), a whirl generator (10) arranged at a distance in front of outlet end (13), which forms a second nozzle with a nozzle axis, of the first mixing tube, and with a second mixing tube (18), the inside cross-section (F2) of which is greater than the inside cross-section (F1) of the first mixing tube and which is arranged concentrally to the outlet end of a first mixing tube which directly produces a burner flame, an inlet end (19) for the burner flame and second suction points (20) for secondary air in the area of the outlet end (13) of the first mixing tube (6), and which extends in the flow direction up to its outlet end (23), characterized in that

   a) between the outlet end (13) of the first mixing tube (6) and the inlet end (19) of the second mixing tube (18) is arranged a filler element (16), which at least substantially fills the radial distance between both tube ends, having an end surface (21), which extends essentially radially to the nozzle axis (A-A) and from which the outlet end (13) of the first mixing tube (6) forming the second nozzle protrudes by a specified measure "s", and that

   b) the second suction points (20) for the secondary air are arranged exclusively in the area of the outlet end (13) of the first mixing tube (6) and radially aligned relative to the nozzle axis (A-A), so that the secondary air essentially hits the starting path of the burner flame vertically, extending in the direction of the nozzle axis, and that the second mixing tube (18) comprises between the second suction points (20) and its outlet end (23) a sealed casing portion (18a) the length of which is at least three times that of the axial extent of the second suction points (20).
2. Burner according to claim 1, characterized in that the filler element (16) is arranged as a rotation-symmetrical part with an inside bore (15) for insertion of the first mixing tube (6) and with at least one outside surface (17) for placing the second mixing tube (18) thereon.
3. Burner according to claim 1, characterized in that the outlet end (13) of the first mixing tube (6) which forms the nozzle protrudes between 4 and 15 mm, preferably between 6 and 12 mm, from the end surface (21) of the filler element (16).
4. Burner according to claim 1, characterized in that the circular end edge (14) of the outlet end (13) of the first mixing tube (6) is inwardly bent and rounded off between 15 and 25%, preferably between 19 and 21%, of the inside diameter of the first mixing tube (6).
5. Burner according to claim 1, characterized in that the ratio of the distance (d) from the end surface (12) of the whirl generator (10) to the end edge (14) of the outlet end of the first mixing tube (6) to the inside diameter (D1) of the first mixing tube is at least 1.0, preferably between 1.1 and 1.5.
6. Burner according to claim 1, characterized in that the whirl generator (10) comprises guide vanes (11) which are spaced around the axis (A-A) of the first mixing tube (6), the application angle of which relative to the axis (A-A) on the outside diameter of the whirl generator is less than 30 degrees, preferably less than 20 degrees, and that the application angle is chosen smaller with increasing burner output and at specified dimensions.
7. Burner according to claim 1, characterized in that the ratio of the inside cross-section (F2) of the second mixing tube (18) to the inside cross-section (F1) of the first mixing tube (6) is between 4.0 and 4.8, preferably approximately 4.3.
8. Burner according to claim 1, characterized in that the second suction points (20) are arranged as axis-parallel slots (24) spaced over the periphery of the second mixing tube (18), and that their end sections (24a), which are oriented towards the filling element (16), at least partially overlap with portion of the first mixing tube (6) which protrudes from the end (21) of the filler element (16).
9. Burner according to claim 8, characterized in that the proportion of all slots (24), as seen in the peripheral direction, relative to the total periphery of the second mixing tube (18) is at least 50%.
10. Burner according to claim 9, characterized in that the ratio of the sum of the cross-sectional surfaces of all slots (24) relative to the inside cross-section "F2" of the second mixing tube (18) is at least 1.2 and preferably between 1.4 and 1.5.
11. Burner according to claim 8, characterized in that the ratio of the length "LS" of each individual slot (24) relative to the length "L" protruding over the filler element (16) of the second mixing tube (18) is between 0.10 and 0.20, preferably between 0.14 and 0.17.
12. Burner according to claim 1, characterized in that the whirl generator (10) is phased on its input side, and that the diameter of the smallest peripheral edge of the phase corresponds essentially with the core diameter (outside diameter minus radial guide-vane length).
13. Burner according to claim 12, characterized in that the application angle of the guide vanes (11) relative to the axis (A-A) is essentially equal the angle between the casing lines of the phase and a plane radial to the axis (A-A).
14. Burner according to claim 1, characterized in that the burner (1, 1a) together with a plurality of identical burners (1b, 1c, 1d, 1...) is attached, with parallel alignment of their axes A-A), to a transverse support (32) and connected to a communal gas-supply line (33) whilst establishing a burner battery (31).
15. Burner according to claim 14, characterized in that the burner battery (31) is provided with mobility rollers (39), the rotary axes of which extend vertically to the burner axes (A-A).
16. Burner according to claim 14, characterized in that on both sides of the burner battery (31) are fitted guide plates (40, 41) the main planes of which extend parallel to the burner axes (A-A).
17. Burner according to claim 16, characterized in that the guide plates (40, 41) are pivotably arranged on the transverse support (32).

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