NOZZLE

Description

[0001] The invention relates to a nozzle with a longitudinal axis and a nozzle end, wherein the nozzle has at least one first channel extending towards the nozzle end for a fluid to be atomized, which opens into a first outlet opening, and at least one second channel extending towards the nozzle end for an atomizing medium, which opens into at least a second outlet opening, wherein a Hartmann generator is arranged opposite the second outlet opening, and wherein the substantially axially directed first outlet opening is opposed by a substantially horizontally extending and pointing away from the nozzle end, which is arranged closer to the nozzle end than the Hartmann generator.

[0002] It is already known to equip a burner nozzle for burning oil, gas, or other flammable fluids (but also other nozzles used for atomizing and injecting one fluid into another, such as an injection nozzle for urea into exhaust gases or flue gases to reduce NOx) with a Hartmann generator at its nozzle tip. This generator sets an atomizing medium into ultrasonic vibrations. As soon as the flammable fluid expelled from the burner nozzle encounters the ultrasonic column of atomizing medium, it is atomized into extremely fine droplets, enabling optimal combustion of the flammable fluid in a combustion chamber into which the burner nozzle opens.

[0003] The shape of the burner nozzle at the nozzle end (i.e., at the end of the nozzle where the fluid to be atomized is jetted out, discharged, sprayed away, etc.) determines the "spray pattern" produced by the burner nozzle, i.e., the shape of the jet exiting the burner nozzle.

[0004] In principle, a distinction is made between two basic types of spray pattern: a jet-shaped spray pattern (in the form of a cone widening away from the burner nozzle) and a tulip-shaped spray pattern (in the form of a bell or round cone widening away from the burner nozzle).

[0005] Particularly for forming a tulip-shaped spray pattern (but also for forming a jet-shaped spray pattern approximating a tulip-shaped pattern), burner nozzles are used in which a stream of combustible fluid, exiting essentially axially from an outlet orifice, flows against a frontal area that extends away from the nozzle end and is essentially horizontal, and is then deflected laterally (i.e., horizontally). The combustible fluid flows from the frontal area into a low-pressure region, the low pressure being generated by the outflow of an atomizing medium from the outlet of a Hartmann generator arranged around the outlet orifice for the combustible fluid. The turbulence of the atomizing medium breaks the combustible fluid into fine droplets.

[0006] Since the atomizing medium is set into ultrasonic vibrations by the Hartmann generator, the droplets of flammable fluid formed in the low-pressure area are also set into vibration. The inertia of the droplets prevents them from oscillating at such high frequencies, so that the droplets break up into even smaller droplets (i.e., they are atomized).

[0007] This otherwise very effective fluid atomization system has the disadvantage that at high flow rates (i.e., at high injection or discharge volumes of the flammable fluid), the outflow velocity of the flammable fluid away from the inlet surface is too high. This results in a low relative velocity between the flammable liquid and the atomizing medium, and consequently, a decrease in the turbulence of the mixture. Furthermore, at high flow rates, the flow of flammable liquid encounters the oscillating column of atomizing medium in a region spaced away from the outlet of the Hartmann generator. This is because, at high flow rates, the flow is concentrated along the inlet surface, which is positioned further towards the nozzle tip than the Hartmann generator. In this spaced region, the ultrasonic vibration is lower than directly at the outlet of the Hartmann generator.

[0008] These two effects result in less atomization of the combustible fluid at high flow rates, leaving larger droplets than at lower flow rates. Larger droplets are undesirable during combustion of the combustible fluid (or during the distribution of one fluid within another, such as when injecting urea into exhaust gas or flue gas), as they lead to incomplete combustion, resulting in coked residues in the exhaust gas or other undesirable effects. To counteract this, the flow rate of the atomizing medium can also be increased, but this is undesirable in many applications.

[0009] A nozzle of this type is known from WO 2011 / 050377 A1.

[0010] The invention is therefore based on the objective of providing a nozzle that does not exhibit the disadvantages of the prior art. In particular, a nozzle is to be provided with which a fluid to be dispensed and atomized can be atomized particularly finely, even at high flow rates.

[0011] According to the invention, this problem is solved with a nozzle having the features of claim 1.

[0012] Preferred and advantageous embodiments of the invention are the subject of the dependent claims.

[0013] According to the invention, the inflow surface has a depression in one of the areas opposite the first outlet opening.

[0014] The depression formed in the inlet surface causes the flow of the fluid to be atomized, which flows from the first outlet opening into the depression, to be deflected not only horizontally but also axially, or rather, redirected axially. As a result, at high flow rates, the flow of the fluid to be atomized no longer runs close to the inlet surface but is directed away from it towards the Hartmann generator, which is positioned closer to the nozzle tip. The fluid to be atomized is drawn in by the negative pressure prevailing at the outlet of the Hartmann generator. Thus, the flow of the fluid to be atomized encounters the vibrating column of the atomizing medium in a region directly adjacent to the outlet of the Hartmann generator, where the ultrasonic vibration is highest. This results in particularly good atomization of the fluid to be atomized.The formation of the depression also promotes the development of turbulence in the fluid being atomized, which further contributes to the finest possible atomization.

[0015] With the nozzle according to the invention, a particularly high throughput of the fluid to be atomized can be achieved even with a low throughput of the atomizing medium, with simultaneously particularly fine atomization.

[0016] The nozzle end is understood to be the end from which the fluid to be atomized is jetted out, released, sprayed, repelled, etc.

[0017] According to the invention, the inflow surface is arranged closer to the nozzle end than the Hartmann generator, wherein, in the case of an inflow surface that is not horizontal but inclined, at least the section of the inflow surface that is radially furthest from the longitudinal axis is arranged closer to the nozzle end than the Hartmann generator.

[0018] Particularly preferred are embodiments of the nozzle in which the first outlet opening has the form of an axial annular gap extending around the longitudinal axis and essentially in the axial direction. Such an axial annular gap enables a particularly uniform distribution of the fluid to be atomized in the direction of the inlet surface or in the direction of the depression formed in the inlet surface. Furthermore, in such an embodiment, the inlet surface can be arranged at the end of a column extending along the longitudinal axis, which, viewed radially, is located within the axial annular gap, resulting in a particularly simple nozzle design.

[0019] However, within the scope of the invention, the first outlet opening can also be a substantially circular outlet hole extending along the longitudinal axis, i.e., a central outlet opening. Such a first outlet opening enables a particularly high throughput of the fluid to be atomized with relatively small dimensions.

[0020] In a preferred embodiment, the recess is an annular deflection groove extending around the longitudinal axis. In this preferred embodiment, the first outlet opening is particularly designed as an axial annular gap.

[0021] In another preferred embodiment, the depression is a substantially circular indentation (or recess or sink), wherein in this embodiment the first outlet opening is in particular a circular outlet hole.

[0022] It is also conceivable to have embodiments in which several first outlet openings are provided. These can, for example, be circular outlet holes arranged in a ring or radially symmetrical manner around the longitudinal axis. A combination of a central circular outlet hole and an annular gap arranged around the outlet hole (and the longitudinal axis), or of several concentric annular gaps, is also conceivable within the scope of the invention.

[0023] Likewise, within the scope of the invention, the inflow surface can have a recess in several of the first outlet openings or, if applicable, in several or all areas opposite the first outlet openings.

[0024] For example, it is possible that a first outlet opening extending centrally along the longitudinal axis is provided together with a further first outlet opening spaced apart from it, annular and extending around the longitudinal axis. In such an embodiment, a centrally arranged indentation and / or at least one deflection groove may be provided.

[0025] Particularly preferred is a rounded recess (for example, a rounded groove). Preferably, such a rounded recess has a circular segment-shaped, and in particular a semicircular, cross-sectional shape. It is also possible within the scope of the invention that the recess is a rounded recess with an elliptical segment-shaped or a hyperbolic cross-section.

[0026] Likewise, within the scope of the invention, it is possible that the recess (e.g., annular deflection groove) is not rounded but chamfered and, for example, has a trapezoidal cross-section.

[0027] Within the scope of the invention, a nozzle is preferred which has a base body into which a distributor insert is inserted, in particular screwed in. In such a nozzle, the flow surface is formed on the distributor insert. An advantage of such nozzles is the replaceability of the distributor insert, which simplifies maintenance and enables a quick change between different spray patterns.

[0028] Within the scope of the invention, it is particularly provided that the first channel has a proximal section extending centrally along the longitudinal axis from the base body into the distributor insert. The proximal section is connected to an annular-shaped distal section via one or more connecting sections, in particular several connecting sections in the form of substantially horizontal bores. The annular-shaped distal section extends around the longitudinal axis, is formed between the base body and the distributor insert therein, and opens into the first outlet opening.

[0029] It is also preferably provided within the scope of the invention that the second channel runs in an annular gap shape in the base body around the longitudinal axis and around the first channel, and that the Hartmann generator, which is formed by a circumferential groove directed essentially radially away from the longitudinal axis, is opposite the second outlet opening, which is directed substantially radially to the longitudinal axis by means of a reversing extension. Such a nozzle design with a distributor insert is generally known and is particularly advantageous in the nozzle according to the invention.

[0030] Furthermore, a preferred embodiment of the nozzle is characterized in which the circumferential groove towards the nozzle tip is bounded by a plate of the Hartmann generator. The plate preferably has the shape of a flat, annular cylinder and possesses a plate surface opposite the inlet surface, preferably extending substantially horizontally. A radially extending annular gap, adjoining the first outlet opening, is formed between the plate surface and the inlet surface. In such an embodiment, the flow of the fluid to be atomized exiting the first outlet opening is guided back axially via the recess (e.g., the deflection groove) so that it encounters the plate surface. The flow of the fluid to be atomized is thereby slowed down and flows or runs close to the plate surface – preferably in a horizontal direction – to the side.Upon exiting the radially extending annular gap, the flow of the medium to be atomized encounters the section of the atomizing medium column directly adjacent to the outlet of the Hartmann generator. In this section, the frequency of the ultrasonic oscillation is highest, resulting in the atomization of the fluid into the finest possible droplets.

[0031] Within the scope of the invention, it is preferred if the distributor insert has a distributor extension extending from the inlet surface towards the nozzle tip, which is cylindrical or spherical segment-shaped, in particular hemispherical. Combustion residues are less likely to adhere to such extensions, so nozzles equipped with them are less prone to coking.

[0032] In particular, the nozzle according to the invention is a burner nozzle and the fluid to be atomized is a flammable fluid, wherein the flammable fluid can be a gas, oil, fuel (such as gasoline, kerosene, or diesel), a flammable waste product, or any other flammable fluid (e.g., an alcohol-containing fluid). With burner nozzles, it is generally particularly important that the fluid to be burned is atomized as finely as possible in order to largely avoid unburned residues in the exhaust gas. However, the nozzle according to the invention can also be used in other application areas where the finest possible atomization of a fluid is desired. For example, the nozzle according to the invention can be used for humidification purposes, for flue gas cooling, or for injecting urea solutions in SNCR systems, or in the chemical or food industries.

[0033] Further details, features and advantages of the invention will become apparent from the following description with reference to the accompanying drawings, in which preferred embodiments are illustrated. These show: Fig. 1 shows a nozzle known from the prior art in a sectional view, wherein the section plane runs along a longitudinal axis of the nozzle; Fig. 2 shows a detail from Fig. 1 In an enlarged view, Fig. 3 shows a nozzle according to the invention in a sectional view, wherein the section plane runs along a longitudinal axis of the nozzle, Fig. 4 shows a detail from Fig. 3 In an enlarged view, Fig. 5 shows a sectional view of an alternative distributor insert of the nozzle according to the invention, and Fig. 6 shows a sectional view of another alternative distributor insert of the nozzle according to the invention.

[0034] Fig. 1Figure 1 shows a nozzle 1 known from the prior art in a lateral sectional view, wherein the section plane runs along a longitudinal axis L of the nozzle 1.

[0035] Consequently, the same reference numerals are used for identical or (functionally) similar components of the nozzle 1 known from the prior art and a nozzle 1 according to the invention.

[0036] The nozzle 1 known from the prior art has a base body 2 that extends in the direction of the longitudinal axis to a nozzle end 3. The nozzle end 3 is the end of the nozzle 1 at which a fluid F to be atomized is injected or expelled in atomized form.

[0037] A distributor insert 4 is inserted into the base body 2. In the illustrated embodiment, the distributor insert 4 is screwed into the base body 2.

[0038] In the nozzle 1 at least a first channel 5 is formed, which runs towards the nozzle end 3, and through which, when the nozzle 1 is in use, the fluid F to be atomized flows towards the nozzle end 3.

[0039] The first channel 5 has a proximal section 6 that extends from the base body 2 into the distributor insert 4. The proximal section 6 runs centrally, i.e., axially along the longitudinal axis L.

[0040] A distal section 7 of the first channel 5 has the form of an annular gap and is formed between the base body 2 and the distributor insert 4. It thus extends axially and around the longitudinal axis L. The distal section 7 opens into a first outlet opening 8, which, in the illustrated embodiment, has the form of an axial annular gap extending around the longitudinal axis L and in the axial direction.

[0041] The proximal section 6 and the distal section 8 of the nozzle 1 are connected to each other via connecting sections 9, the connecting sections 9 being formed by radially extending bores in the distributor insert 4.

[0042] In the nozzle 1, at least one additional channel 11 is formed, which also extends towards the nozzle end 3 and through which an atomizing medium Z flows when the nozzle 1 is used as intended. The atomizing medium Z can, for example, be compressed air.

[0043] The second channel 11 has the form of an annular gap, runs around the longitudinal axis L and around the first channel 5 and opens into a second outlet opening 12.

[0044] The second channel 11 runs mostly in an axial direction, but shortly before the second outlet opening 12 it has a curvature towards the longitudinal axis L, so that the second outlet opening 12 is essentially directed in a radial direction and towards the longitudinal axis L.

[0045] A Hartmann generator 13 is formed or arranged in or on the base body 2 of the nozzle 1. The Hartmann generator 13 is formed by a circumferential groove that runs around the longitudinal axis L and around the first channel 5 and is directed essentially radially away from the longitudinal axis L.

[0046] The Hartmann generator 13 is essentially arranged opposite the second outlet opening 12, or the second outlet opening 12 leads directly into the Hartmann generator 13.

[0047] The distributor insert 4 has an insertion area 14, with which the distributor insert 4 is inserted into the base body 2, in particular screwed in.

[0048] Towards the nozzle end 3, the distributor insert 4 has a distributor extension 15 on which a flow surface 16 is formed, directed away from the nozzle end 3 and towards the first outlet opening 8. The flow surface 16 of the inserted distributor insert 4 is opposite the first outlet opening 8 (for the fluid F to be atomized).

[0049] In the illustrated embodiment, the inlet surface 16 is annular, extends around the longitudinal axis L, and reaches radially. The inlet surface 16 is located closer to the outlet nozzle 3 than the Hartmann generator 13.

[0050] In the illustrated embodiment, the distributor extension 15 has the shape of a hemisphere extending from the inlet surface 16 to the nozzle tip 3. The distributor insert 4 is suitable for producing a "tulip-shaped" spray pattern and is less prone to "coking".

[0051] The circumferential groove forming the Hartmann generator 13 is bounded towards the nozzle end 3 by a plate 17, which projects radially and away from the longitudinal axis L in a flange-like manner. The plate 17 has the shape of a flat, annular cylinder and has an annular surface 18 on its side facing the nozzle end 3.

[0052] Between the plate surface 18 and the opposite flow surface 16 a radial annular gap 19 is formed extending in a radial direction and around the longitudinal axis L, which connects directly to the first channel 5.

[0053] As in Fig. 1 and in Fig. 2(a detail from Fig. 1 (as shown in enlarged view), the atomizing medium Z flows through the second channel 11 towards the nozzle end 3, exits radially and towards the longitudinal axis L from the second outlet opening 12 and flows from the second outlet opening 12 directly into the Hartmann generator 13 arranged opposite it, which is designed as a circumferential groove.

[0054] Due to the operating principle of the Hartmann generator 13, which is not described in detail here, the atomizing medium Z is set into ultrasonic vibrations and emerges from an outlet opening 21 of the Hartmann generator 13 as an ultrasonic "column" (i.e., as a column of gas or gas mixture, such as an air column). The outlet opening 21 of the Hartmann generator 13 is bounded in the direction of the outflow end 3 by the plate 17 of the Hartmann generator 13 and in the other direction by the second outlet opening 12.

[0055] The fluid F to be atomized, on the other hand, first flows through the proximal section 6 of the first channel 5, and from there via the connecting sections 9 into the distal section 7 of the first channel 5. Through the first outlet opening 8, the fluid F to be atomized flows essentially in an axial direction and towards the nozzle end 3 out of the first channel 5.

[0056] The fluid F to be atomized, exiting or flowing from the first outlet opening 8, flows (or impacts) against the inlet surface 16 and is deflected by it in a radial direction, so that it is guided radially through the radial annular gap 19 and away from the longitudinal axis L. Particularly at high outlet velocities, i.e., at high flow rates of the fluid F to be atomized, it flows close to the inlet surface 16.

[0057] Upon exiting the radial annular gap 19, the fluid F to be atomized encounters the column of the atomizing medium Z, which is set into ultrasonic vibrations. The ultrasonic vibrations atomize the fluid F into the finest droplets, which, together with the column of the atomizing medium Z, are jetted (i.e., sprayed, transported, blasted, etc.) away from the nozzle end 3.

[0058] Particularly at high throughputs, the fluid F exiting the radial annular gap 19, which is to be atomized, strikes the column of the atomizing medium Z, which is set into ultrasonic vibrations, at a distance from the outlet opening 21, since the fluid F to be atomized flows close to the inflow surface 16, and the inflow surface 16 is arranged further towards the nozzle end 3 than the Hartmann generator 13.

[0059] The Figs. 3 and 4show a nozzle 1 according to the invention, also in a side sectional view or in a view showing a detail from this sectional view, wherein also in the Figs. 3 and 4 the cutting plane runs along a longitudinal axis L of the nozzle 1 according to the invention.

[0060] The nozzle 1 known from the prior art differs from the nozzle 1 according to the invention only in the feature according to the invention, which is why only this distinguishing feature and the resulting effect will be described separately below.

[0061] During the Figs. 3 and 4 In the illustrated embodiment, the inflow surface 16 of the distributor insert 4 of the nozzle 1 according to the invention has a recess 22 in the form of an annular deflecting groove extending around the longitudinal axis L in an area directly opposite the first outlet opening 8.

[0062] In the illustrated embodiment, the recess 22 designed as a deflection groove is a rounded groove, wherein the recess 22 designed as a rounded deflection groove has a semicircular cross-section.

[0063] As in Fig. 4 As shown in detail, the fluid F exiting or flowing out of the first outlet opening 8, which is to be atomized, flows into the recess 22 designed as a deflection groove and is guided or deflected by this in an axial direction away from the nozzle end 3 and back to the plate 17 of the Hartmann generator 13.

[0064] The fluid F to be atomized is not only slowed down by being deflected towards the plate 17, but also flows (or streams), especially at high throughputs of the fluid F to be atomized, close to the plate surface 18 in a radial direction through the radial annular gap 19 and out of it.

[0065] By deflecting the fluid F to be atomized in an axial direction (especially since it now flows over the plate surface 18, which is further away from the nozzle end 3 than the inlet surface 16), it strikes the ultrasonically vibrating column of the atomizing medium Z at a lesser distance from the outlet opening 21 of the Hartmann generator 13 than in the Figs. 1 and 2 This is the case with nozzle 1, which is known from the prior art. Ideally, the fluid to be atomized strikes the oscillating gas or gas mixture column consisting of the atomizing medium Z directly at the outlet opening 21 of the Hartmann generator 13.

[0066] Since the frequency of the ultrasonic oscillation of the column of the atomizing medium Z is highest directly at the outlet opening 21 of the Hartmann generator 13 and decreases away from the outlet opening 21, the fluid F to be atomized, in the nozzle according to the invention, enters a section or region of the column of the atomizing medium Z that oscillates at a higher frequency than the fluid F to be atomized in the nozzle 1 known from the prior art. The fluid F to be atomized is thus atomized into finer droplets than is possible with a nozzle 1 known from the prior art.

[0067] Fig. 5 Figure 1 shows another embodiment of the distributor insert 4 of the nozzle 1 according to the invention, which is possible within the scope of the invention. In this distributor insert 4 as well, the flow surface 16 opposite the first channel 5 (or the first outlet opening 8) in the installed state of the distributor insert 4 has the recess 22 designed as a deflecting groove.

[0068] The distributor insert 4 has a distributor extension 15 in the form of a flat cylinder extending towards the nozzle end 3 and is suitable for generating a "jet-shaped" spray pattern.

[0069] Fig. 6 Figure 1 shows a further embodiment of the distributor insert 4 of the nozzle 1 according to the invention, which is possible within the scope of the invention. In nozzles 1 according to the invention that have such a distributor insert 4, the first channel 5 has no distal section 7 and no connecting sections 9. The first channel 5 has only the proximal section 6 extending along the longitudinal axis L, which reaches to the first outlet opening 8, designed as a circular outlet hole. The inflow surface 16 opposite the first outlet opening 8 has the recess 22, which is designed in the form of an indentation or depression.

[0070] The indentation 22 also serves to direct or redirect the fluid F, which is to be atomized and exits from the first outlet opening 8, in an axial direction away from the nozzle end 3 and towards the plate 17 of the Hartmann generator 13.

[0071] Unlike the embodiments according to the Fig. 3, 4 and 5 is the distributor extension 15 in the Fig. 6 The distributor insert 4 shown is not arranged on a centrally and column-shaped section of the distributor insert 4, but on several web elements 23 arranged radially symmetrically to the longitudinal axis L and radially spaced from the longitudinal axis L. In the Fig. 6 In the illustrated embodiment, two opposing web elements 23 are provided for this purpose, wherein in Fig. 6 only one of the web elements 23 is visible, since the section plane is perpendicular to a plane in which the web elements 23 are arranged.

[0072] In the Fig. 6 In the illustrated embodiment, the recess 22, which is designed as an indentation, is not rounded and has a rectangular cross-section. However, the recess 22 can also be rounded. Likewise, the recess 22 can be rounded in the [context missing] Fig. 3, 4 and 5 The illustrated embodiments may also have a rectangular or polygonal cross-sectional shape.

[0073] The features of the embodiments of differently designed distributor inserts 4 shown in the figures can also be adequately transferred to nozzles 1 according to the invention, in which the nozzle 1 has a base body 2 without a separate distributor insert 4, i.e., in which the flow surface 16 with the recess 22 (which is, for example, a deflecting groove or an indentation) is formed directly on the base body 2.

[0074] Combinations of features of individual embodiments depicted in the figures, which are not shown, are also conceivable within the scope of the invention. For example, the one shown in Fig. 6 The distributor insert 4 shown has a distributor extension 15 in the form of a flat cylinder extending towards the nozzle end 3. Reference symbol list

[0075] 1 Nozzle 2 Base body 3 Nozzle tip 4 Distributor insert 5 First channel 6 Proximal section 7 Distal section 8 First outlet opening 9 Connecting section 10--- 11 Second channel 12 Second outlet opening 13 Hartmann generator 14 Insertion area 15 Distributor extension 16 Inlet area 17 Disc 18 Disc area 19 Radial annular gap 20--- 21 Outlet opening 22 Recess Longitudinal axis, fluid to be atomized, atomizing medium

Claims

1. Nozzle (1) with a longitudinal axis (L) and an ejection end (3), wherein the nozzle (1) has at least one first channel (5) for a fluid (F) to be atomized, which opens into a first outlet opening (8), and at least one second channel (11) extending in the direction of the ejection end (3) for an atomizing medium (Z), which opens into at least one second outlet opening (12), wherein a Hartmann generator (13) is arranged opposite the second outlet opening (12) , and wherein the first outlet opening (8), which is directed essentially in the axial direction, is opposed by an inflow surface (16) which extends essentially horizontally and points away from the ejection end (3) and which is arranged closer to the ejection end (3) than the Hartmann generator (13), characterized in that the inflow surface (16) has a recess (22) in an area opposite the first outlet opening (8).

2. Nozzle according to claim 1, characterized in that the first outlet opening (8) has the shape of an axial ring gap extending around the longitudinal axis (L) and essentially in the axial direction, or an essentially circular outlet hole extending along the longitudinal axis (L).

3. Nozzle according to claim 1 or 2, characterized in that the recess (22) is an annular deflection groove extending around the longitudinal axis (L), or that the recess (22) is a substantially circular indentation.

4. Nozzle according to one of claims 1 to 3, characterized in that the recess (22) is a rounded recess, preferably with a circular segment-shaped, in particular a semicircular cross-section.

5. Nozzle according to one of claims 1 to 4, characterized in that the nozzle (1) has a base body (2) into which a distributor insert (4) is inserted, in particular screwed in, and that the inflow surface (16) is formed on the distributor insert (4).

6. Nozzle according to claim 5, characterized in that the first channel (8) has a proximal section (6) which runs centrally along the longitudinal axis (L) from the base body (2) into the distributor insert (4), and a annular gap-shaped distal section (7) connected to the proximal section (6) via one or more connecting sections (9), which runs around the longitudinal axis (L), wherein the annular gap-shaped distal section (7) is formed between the base body (2) and the distributor insert (4) inserted therein and opens into the first outlet opening (8).

7. Nozzle according to one of claims 5 or 6, characterized in that the second channel (11) runs in an annular gap shape in the base body (2) and around the longitudinal axis (L) and around the first channel (8), and that the second outlet opening (12), which is directed substantially radially towards the longitudinal axis (L), is opposite the Hartmann generator (13), which is formed by a circumferential groove directed substantially radially away from the longitudinal axis (L).

8. Nozzle according to claim 7, characterized in that the circumferential groove forming the Hartmann generator (13) is bounded towards the ejection end (3) by a plate (17), which preferably has the shape of a flat, circular ring-shaped cylinder, and which has a plate surface (18) opposite the inflow surface (16), preferably extending substantially horizontally, and that a radial annular gap (19) extending in the radial direction and adjoining the first outlet opening (8) is formed between the plate surface (18) and the inflow surface (16).

9. Nozzle according to one of claims 5 to 8, characterized in that the distributor insert (4) has a distributor extension (15) extending from the inflow surface (16) toward the ejection end (3), which is cylindrical or spherical segment-shaped, in particular hemispherical.

10. Nozzle according to one of claims 1 to 9, characterized in that the nozzle (1) is a burner nozzle and the fluid (F) to be atomized is a combustible fluid, in particular gas, oil, or a combustible waste product.