JP7274891B2 - gas atomizing burner nozzle - Google Patents

Description

The present invention has a cylindrical portion having an ejection passage inside which an atomized mixed fuel in which an atomized liquid fuel and a gas fuel are mixed flows. A first nozzle portion provided with a main ejection hole for ejecting atomized mixed fuel in the axial direction of the ejection passage, a liquid fuel ejection hole for ejecting liquid fuel at the base end of the ejection passage, and the liquid fuel ejection hole a gas atomizing burner nozzle provided with a gas fuel ejection hole for ejecting gas fuel for atomizing liquid fuel ejected from an ejection path at the base end of the ejection passage;

Such a gas atomizing burner nozzle is used for a gas atomizing burner that atomizes and burns liquid fuel with gas fuel, and this gas atomizing burner is used for heating objects to be heated such as lime kilns for papermaking and glass melting furnaces. used in Various types of liquid fuels are used, such as heavy oil, light oil, kerosene, and reclaimed oil from waste oil. In heating the object to be heated such as, the energy cost is reduced.

This gas atomizing burner atomizes the liquid fuel jetted from the liquid fuel jetting holes of the second nozzle section by the gas fuel jetting from the gas fuel jetting holes of the second nozzle section while passing through the jetting path of the first nozzle section. By causing the fuel to flow, mixing the atomized liquid fuel and the gas fuel in the flow process, and ejecting the mixed fuel (hereinafter sometimes referred to as atomized mixed fuel) from the main ejection hole It is designed to burn.

In such a gas atomizing burner nozzle, conventionally, the tip of the cylindrical portion of the first nozzle portion is fully opened, and the leading end opening having the same diameter as the ejection passage opening at the tip of the cylindrical portion is used as the main ejection hole. .
Then, the entire amount of the atomized mixed fuel flowing through the ejection passage is ejected from the main ejection hole having the same diameter as the ejection passage at the tip of the ejection passage in the axial direction of the ejection passage and burned. (See Patent Document 1, for example).

JP 2018-162927 A

By the way, in such a gas atomizing burner, there is a demand to make the temperature distribution in the furnace a predetermined temperature distribution according to the heating conditions of the object to be heated while ensuring a predetermined combustion amount. For example, in order to form a temperature distribution in which the high temperature region is closer to the near side (gas atomizing burner side) in the furnace, the length of the formed flame needs to be shortened.
However, the first nozzle portion of the conventional gas atomizing burner nozzle is configured to eject the entire amount of the atomized mixed fuel flowing through the ejection passage from the main ejection hole having the same diameter as the ejection passage in the axial direction of the ejection passage. As long as the combustion amount of the gas atomizing burner is the same, it is difficult to change the shape of the flame that is formed.
Therefore, it has not been possible to meet the demand for a predetermined temperature distribution in the furnace.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a gas atomizing burner nozzle capable of setting the temperature distribution in the furnace to a predetermined temperature distribution.

A gas atomizing burner nozzle according to the present invention for achieving the above object has a cylindrical portion having an ejection passage inside which an atomized mixed fuel in which an atomized liquid fuel and a gas fuel are mixed flows. a first nozzle portion provided at the tip of the ejection passage with a main ejection hole for ejecting the atomized mixed fuel flowing through the ejection passage in the axial direction of the ejection passage;
A liquid fuel ejection hole for ejecting liquid fuel to the base end of the ejection passage, and a gas fuel for spraying gas fuel for atomizing the liquid fuel ejected from the liquid fuel ejection hole to the base end of the ejection passage. A gas atomizing burner nozzle comprising a second nozzle part provided with a jet hole, characterized by:
A plurality of sub-ejection holes communicating with the ejection path are provided in the peripheral wall of the cylindrical portion of the first nozzle part in a state of being arranged in a ring when viewed in the direction of the ejection path axis along the axis of the ejection path,
the axial center of each of the plurality of secondary ejection holes is tapered such that the axial center of each of the plurality of secondary ejection holes moves away from the axial center of the ejection path in the radial direction of the cylindrical portion toward the front in the axial direction of the ejection path;
An annular sub-ejection hole group in which a plurality of the sub-ejection holes are arranged annularly when viewed in the ejection path axis direction at the same location in the ejection path axis direction is formed in a plurality of the ejection path axis directions on the peripheral wall of the cylindrical portion. the annular secondary ejection hole group is provided in a plurality of stages in the axial direction of the ejection path on the peripheral wall of the cylindrical portion,
Of the plurality of stages of the annular sub-jet hole group, the plurality of sub-jet holes in the foremost annular sub-jet hole group in the jet path axial direction have tip openings that are located on the peripheral wall of the cylindrical portion. is provided in a state of opening in a portion corresponding to the front end surface facing forward in the axial direction of the ejection passage,
The axial centers of the plurality of secondary ejection holes in the foremost annular secondary ejection hole group in the direction of the axial center of the ejection path are arranged in a circular shape in which the axial centers of the plurality of secondary ejection holes are displaced in the same direction in the circumferential direction of the cylindrical portion toward the front in the direction of the axis of the ejection path. and
The axial centers of the plurality of sub-jet holes in the annular sub-jet hole group other than the foremost annular sub-jet hole group in the direction of the jet passage axis are in the cylindrical shape when viewed in the radial direction of the cylindrical portion. It is in a state of being overlapped with the axis of the part .

According to the above characteristic configuration, part of the atomized mixed fuel flowing through the ejection passage is ejected from the main ejection hole in the axial direction of the ejection passage, and the remaining amount of the atomized mixed fuel flowing through the ejection passage is The atomized mixed fuel ejected from the main ejection hole and the atomized mixed fuel ejected from the plurality of secondary ejection holes are ejected from the plurality of secondary ejection holes annularly arranged around the main ejection hole in a diverging shape, Burn in the furnace.

That is, the cross-sectional area of the main ejection hole, the number of sub-ejection holes, and the plurality of sub-ejections related to the ratio of the atomized mixed fuel ejected from the main ejection hole and the atomized mixed fuel ejected from the plurality of sub-ejection holes By variously setting the cross-sectional area of each hole and the angle at which the axis of each of the plurality of sub-ejection holes diverges (hereinafter sometimes referred to as the divergence angle), the It is possible to adjust the length and thickness of the formed flame. By the way, by ejecting the atomized mixed fuel flowing through the ejection path from the main ejection hole and a plurality of sub-ejection holes, compared with the configuration in which the fuel is ejected only from the main ejection hole, the flame formed in the furnace is reduced. Since it is easy to shorten and thicken the length, it is easy to form a temperature distribution in which the high temperature region is brought closer to the front side of the furnace.
By adjusting the length and thickness of the flame formed in the furnace, the temperature distribution formed in the furnace can be adjusted.
Therefore, it is possible to provide a gas atomizing burner nozzle capable of setting the temperature distribution in the furnace to a predetermined temperature distribution.

Furthermore, according to the above characteristic configuration, a part of the atomized mixed fuel flowing through the ejection passage is ejected from the main ejection hole in the axial direction of the ejection passage, and the remaining amount of the atomized mixed fuel flowing through the ejection passage is is ejected from the plurality of annularly arranged sub-ejection holes of each of the plurality of stages of the annular sub-ejection hole groups in a widening manner around the atomized mixed fuel ejected from the main ejection hole, and is ejected from the main ejection hole. The atomized mixed fuel and the atomized mixed fuel jetted from the plurality of sub-jet holes of each of the multi-stage annular sub-jet hole groups are combusted in the furnace.

In other words, the cross-sectional area of the main ejection hole, which is related to the ratio of the atomized mixed fuel ejected from the main ejection hole and the atomized mixed fuel ejected from the multistage annular sub-ejection hole group, is arranged in the ejection passage axis direction. The number of stages of the annular secondary ejection hole group, the number of secondary ejection holes of each annular secondary ejection hole group, the cross-sectional area of each of the plurality of secondary ejection holes of each annular secondary ejection hole group, and the plurality of secondary ejection holes of each annular secondary ejection hole group The length and thickness of the flame formed in the furnace can be adjusted by variously setting the angle of divergence of each ejection hole.
In particular, since the annular secondary ejection hole group is provided in a plurality of stages in the axial direction of the ejection path, it is effective in shortening and widening the shape of the flame formed in the furnace.
Therefore, it is possible to provide a gas atomizing burner nozzle that is suitable for forming a temperature distribution in which the high temperature region is positioned relatively to the near side.

Furthermore, according to the above characteristic configuration, the tip opening of each of the plurality of sub-jet holes in the foremost annular sub-jet hole group is provided on the tip face of the peripheral wall of the cylindrical portion, and the tip face is positioned in the furnace. Since it faces the direction in which the flame is formed, the tip surface functions as a flame holding function when the atomized mixed fuel jetted from each of the plurality of sub-jet holes of the foremost annular sub-jet hole group burns. can be effectively demonstrated.
That is, the atomized mixed fuel ejected from each of the plurality of sub-ejection holes of the foremost annular sub-ejection hole group is flame-stabilized by the tip surface of the peripheral wall of the cylindrical portion and burns stably, thereby stably forming a flame. be done. The flame holding effect of the flame thus stably formed enables stable formation of a relatively short and thick flame as a whole.
Therefore, it is possible to more stably form a temperature distribution in which the high temperature region is positioned relatively to the near side.

A further characteristic configuration of the gas atomizing burner nozzle according to the present invention is that a main ejection hole forming body is provided in a state in which the tip opening of the cylindrical portion is closed,
The main point is that the main ejection hole is formed in the main ejection hole formation body so that the cross-sectional area of the main ejection hole is smaller than the cross-sectional area of the ejection passage.

According to the above characteristic configuration, since the cross-sectional area of the main injection hole is smaller than the cross-sectional area of the injection passage, the resistance when the atomized mixed fuel is injected from the main injection hole is increased, so that the injection passage flows through the injection passage. Thus, the atomized mixed fuel is easily ejected from the plurality of sub-ejection holes arranged in a ring.
Since the ejection of the atomized mixed fuel from the plurality of annularly arranged secondary ejection holes effectively shortens and thickens the length of the flame, It is effective in shortening and widening the shape of the flame formed in the furnace by increasing the ejection amount from the plurality of sub-ejection holes arranged in a ring.
Therefore, it is possible to provide a gas atomizing burner nozzle that is suitable for forming a temperature distribution in which the high temperature region is positioned relatively to the near side.

A further characteristic configuration of the gas atomizing burner nozzle according to the present invention is whether the total sub-jet hole area, which is the sum of the cross-sectional areas of all the sub-jet holes, is equal to the main jet hole area, which is the cross-sectional area of the main jet holes. The point is that the area is larger than the main ejection hole area.

According to the above characteristic configuration, since the total area of the secondary ejection holes is equal to or larger than the area of the main ejection holes, of the atomized mixed fuel flowing through the ejection path, the plurality of secondary ejection holes arranged in an annular shape. Since the amount of spray from the holes is relatively large, the shape of the flame formed in the furnace can be made shorter and thicker.
Therefore, it is possible to form a temperature distribution in which the high temperature region is located further forward.

A further characteristic configuration of the gas atomizing burner nozzle according to the present invention is that the ratio of the total area of the secondary ejection holes to the area of the main ejection holes is 1-21.

The inventors of the present invention have made intensive studies in order to accurately shorten and thicken the shape of the flame formed in the furnace, and have determined that the ratio of the total secondary ejection hole area to the main ejection hole area is 1 to 21. It has been found that the shape of the flame formed in the furnace can be accurately shortened and thickened by setting it in between.
In other words, setting the ratio of the total sub-spout area to the main spout area to 1 or more is effective in shortening and thickening the shape of the flame, but if the ratio is too large, the length of the flame will be shortened. tend to be longer. Therefore, by setting the ratio of the total area of the secondary ejection holes to the area of the main ejection holes between 1 and 21, the shape of the flame formed in the furnace can be appropriately shortened and thickened.
Therefore, it is possible to accurately form a temperature distribution in which the high temperature region is located on the front side.

A further characteristic configuration of the gas atomizing burner nozzle according to the present invention is provided in a state in which a plurality of the liquid fuel ejection holes are arranged in an annular shape when viewed in the axial direction of the ejection path,
The plurality of gas fuel ejection holes are provided in a state of being arranged in a ring around the outer peripheral portion of the plurality of liquid fuel ejection holes arranged in a ring.

According to the above characteristic configuration, since the liquid fuel is ejected from the plurality of liquid fuel ejection holes, the surface area of the jet flow of the liquid fuel is increased, and the gas fuel contacts a wider range of the jet flow of the liquid fuel. As a result, the atomization performance of atomizing the liquid fuel with the gas fuel is improved, the atomization of the liquid fuel is further promoted, and the mixing of the atomized liquid fuel and the gas fuel is further promoted.
As a result, the liquid fuel is atomized more evenly over the entire area, and the atomized mixed fuel in which the atomized liquid fuel and the gas fuel are more evenly mixed is ejected, and the atomized liquid fuel is used for combustion. Air can easily come into contact with a wider area, and the flammability of gas fuel works over a wider area, so it is possible to reduce the ratio of gas fuel injection amount to the total fuel injection amount while maintaining stable combustion. becomes.
Therefore, it is possible to reduce the ratio of the gas fuel injection amount to the total fuel injection amount while maintaining stable combustion, thereby reducing the energy cost.

FIG. 2 is a longitudinal development view of a medium flame type gas atomizing burner. Fig. 2 is an exploded perspective view of a main part of a medium flame type gas atomizing burner; 1 is a front view of a medium flame type gas atomized burner. FIG. It is a front view of a 2nd nozzle. FIG. 2 is a longitudinal development view of a short-flame A-type gas atomized burner. Fig. 2 is an exploded perspective view of a main part of a short-flame A-type gas atomizing burner; 1 is a front view of a short-flame A-type gas atomized burner; FIG. FIG. 2 is a longitudinal development view of a short-flame B-type gas atomizing burner. Fig. 2 is an exploded perspective view of a main part of a short-flame B-type gas atomizing burner; 1 is a front view of a short-flame B-type gas atomizing burner; FIG. It is a figure which shows the result of an evaluation test.

An embodiment of the present invention will be described below based on the drawings.
In the following description, a medium flame type gas atomizing burner and a short flame type A gas atomizing burner are shown. not included in
As shown in FIG. 1, the gas atomizing burner mixes the atomized liquid fuel and the gas fuel while atomizing the liquid fuel with the gas fuel, and produces an atomized mixture of the gas fuel and the atomized liquid fuel. A gas atomizing burner nozzle 1 for ejecting mixed fuel, a double pipe member 2 for supplying liquid fuel and gas fuel to the gas atomizing burner nozzle 1, and water as a cooling medium to flow to cool the gas atomizing burner nozzle 1. It is configured to include a water-cooling jacket 3 and the like.

This gas atomizing burner is used, for example, in various furnaces such as glass melting furnaces and lime kilns for papermaking. Since the manner in which the gas atomizing burner is installed in the furnace is well known, detailed description and illustrations will be omitted, and a brief description will be given.
The furnace walls of the furnace are provided with air passages for supplying combustion air into the furnace.
A so-called underport type gas atomizing burner is provided below the air passage in the furnace wall so that the atomized mixed fuel ejected from the gas atomizing burner nozzle 1 is burned by the combustion air supplied from the air passage. Alternatively, it is configured as a so-called through port type by being provided in the air passage.

As shown in FIGS. 1 to 3, the gas atomizing burner nozzle 1 has a cylindrical portion 42 having an ejection passage 41 inside which an atomized mixed fuel in which an atomized liquid fuel and a gas fuel are mixed flows. , a first nozzle (an example of a first nozzle portion) provided at the tip of the ejection path 41, the main ejection hole 43 for ejecting the atomized mixed fuel flowing through the ejection path 41 in the direction of the axis P of the ejection path 41 ) 4, a liquid fuel ejection hole 51 for ejecting liquid fuel at the base end of the ejection passage 41, and a gas fuel for atomizing the liquid fuel ejected from the liquid fuel ejection hole 51 at the base of the ejection passage 41. and a second nozzle (an example of a second nozzle portion) 5 provided with a gaseous fuel ejection hole 52 for ejecting gas at the end.

As shown in FIGS. 1 to 3, the water cooling jacket 3 has a substantially cylindrical shape capable of accommodating the gas atomizing burner nozzle 1 therein, and is a burner cap for integrally assembling a plurality of members constituting the gas atomizing burner. It is configured to be used also for
In this embodiment, the gas atomizing burner includes a water-cooling jacket 3 that also serves as a burner cap, a first nozzle 4 that is fitted in the water-cooling jacket 3 with its tip portion protruding, and a tip surface. a second nozzle 5 placed in contact with the base end surface of the first nozzle 4; The distal end of the inner tube 21 is fitted inside the proximal end of the second nozzle 5 , and the distal end of the outer tube 22 is screwed to the proximal end of the inner peripheral surface of the tubular connecting member 6 . It is configured with a double pipe member 2 and the like that are assembled in a folded state.

Each part of the gas atomizing burner will be explained below.
As shown in FIGS. 1 to 4, the water-cooling jacket 3, the first nozzle 4, the second nozzle 5, the cylindrical connecting member 6 and the double pipe member 2 are assembled coaxially. The axis of the ejection path 41 inside the cylindrical portion 42 (hereinafter sometimes referred to as the ejection path axis) includes the first nozzle 4, the water cooling jacket 3, the second nozzle 5, the tubular connecting member 6 and the double It is also the axial center of the pipe member 2, and the axial center of each of these members is indicated by symbol P in each figure.

In the present invention, the peripheral wall 42w of the cylindrical portion 42 of the first nozzle 4 is provided with a plurality of secondary ejection holes 44 communicating with the ejection passage 41. , and the axis Q of each of the plurality of secondary ejection holes 44 diverges in the radial direction of the cylindrical portion 42 from the axis P of the ejection path 41 toward the front in the direction of the axis P of the ejection path. be.
In addition, a main ejection hole forming body 45 is provided in a state in which the tip opening of the cylindrical portion 42 is closed. is formed in a state of being small.

The gas atomizing burner nozzle 1 according to the present invention has a It is possible to vary the length and thickness of the flame F that can be formed. Therefore, in this embodiment, by setting three types of first nozzles 4 having different lengths of flame F that can be formed, three types of gas atomizing burner nozzle 1 having different lengths of flame F that can be formed will be explained. do.

Each of the three types of gas atomizing burner nozzles 1 is equipped with a first nozzle 4 capable of forming a flame F having a shorter length than the previously described conventional configuration. Among the types of first nozzles 4, the one capable of forming the longest flame F is the medium flame type (see FIGS. 1 to 3), and the one capable of forming the second longest flame F is the short flame A type (see FIG. 5). to FIG. 7), and that capable of forming the shortest flame F is called a short flame type B (see FIGS. 8 to 10). The gas atomizing burner nozzles 1 equipped with the three types of first nozzles 4 are also referred to as medium flame type, short flame type A, and short flame type B, respectively.

First, based on FIGS. 1 to 3, FIGS. 5 to 7, and FIGS. 8 to 10, the common configuration of the three types of first nozzles 4 will be described.
The cylindrical portion 42 of the first nozzle 4 has a two-stepped shape and is coaxially provided with a large diameter portion 42b having a larger diameter than the distal end side and a shorter length in the direction of the axis P at the proximal end. In the embodiment, the first nozzle 4 is configured by the cylindrical portion 42 itself. That is, the first nozzle 4 is configured to have a two-stage cylindrical outer shape having a large-diameter portion 42b coaxially on the base end side.
The ejection passage 41 inside the cylindrical portion 42 is also configured to have a larger diameter portion coaxially at the proximal end than the distal end side, and the proximal end portion is the liquid fuel of the second nozzle. A receiving portion 41g is configured to receive the liquid fuel ejected from the ejection holes 51 and the gas fuel ejected from the gas fuel ejection holes 52 .

In the three types of first nozzles 4, among the dimensions of each part, the common dimensions are the total length of the cylindrical portion 42 in the direction of the axis P and the length of the large diameter portion 42b of the cylindrical portion 42 in the direction of the axis P. These are the length, the diameter of the cylindrical portion 42, the diameter of the large diameter portion 42b of the cylindrical portion 42, the diameter of the jet passage 41, and the diameter of the receiving portion 41g of the jet passage 41.
Incidentally, as an example of these common dimensions, the total length of the cylindrical portion 42 is 100 mm, the length of the large diameter portion 42b of the cylindrical portion 42 is 20 mm, the diameter of the cylindrical portion 42 is 44.5 mm, and the diameter of the cylindrical portion 42 is 44.5 mm. The diameter of the large diameter portion 42b of is 52 mm, the diameter of the ejection path 41 is 20 mm, and the diameter of the receiving portion 41g of the ejection path 41 is 29 mm.

Next, based on FIGS. 1 to 3 and FIGS. 5 to 7, the common configuration of the two types of first nozzles 4, medium flame type and short flame A type, will be described.
The axis Q of each of the plurality of secondary ejection holes 44 of the first nozzle 4 diverges in the same direction in the circumferential direction of the cylindrical portion 42 toward the front in the direction of the ejection path axis P, in addition to the above-described widening shape. It is spiral.
Furthermore, a plurality of secondary ejection holes 44 are provided with respective tip openings 44a opening in portions corresponding to tip surfaces 42s of the peripheral wall 42w of the cylindrical portion 42, which face forward in the direction of the ejection path axis P. there is

As shown in FIGS. 1 to 3, the medium flame type first nozzle 4 has 12 secondary ejection holes 44 arranged in a ring at equal intervals when viewed in the direction of the ejection path axis P. As shown in FIGS. 5 to 7, the short-flame A-type first nozzle 4 has eight secondary ejection holes 44 arranged in a ring at equal intervals when viewed in the direction of the ejection path axis P. .

As shown in FIGS. 3 and 7, a circle (hereinafter referred to as a sub-ejection hole The diameter (PCD) of C1, which may be referred to as an array circle, is the same between the first nozzles 4 of medium flame type and short flame A type. Incidentally, in both the medium flame type and short flame A type first nozzles 4, the PCD of the sub-ejection hole arrangement circle C1 of the plurality of sub-ejection holes 44 is, for example, 32 mm.

The medium flame type first nozzle 4 is shown in FIG. 1, and the short flame A type first nozzle 4 is shown in FIG. 4, the angle α at which the axial center Q of each of the plurality of sub-ejection holes 44 expands (hereinafter sometimes referred to as the angle of expansion) is the same for all the sub-ejections 44. , and an example of the divergence angle α thereof is, for example, 30°.

The medium flame type first nozzle 4 is shown in FIG. 3, and the short flame A type first nozzle 4 is shown in FIG. In any one nozzle 4, the angle β at which the axis Q of each of the sub-ejection holes 44 is swirled (hereinafter sometimes referred to as the swirl angle) is the same for all the sub-ejections 44. An example of the turning angle β is 15°, for example.

In the medium-flame first nozzle 4, all of the plurality of secondary ejection holes 44 have the same diameter (diameter of a circular hole in a cross section perpendicular to the axis Q; the same shall apply hereinafter). In the first nozzle 4 of , all of the plurality of sub ejection holes 44 have the same diameter.
However, the medium-flame first nozzle 4 and the short-flame A-type first nozzle 4 have different diameters of the sub-ejection holes 44 , and the diameter of the sub-ejection hole 44 is the same as that of the short-flame A-type first nozzle 4 . is large.
Incidentally, as an example of the diameter of the sub-jet hole 44, the medium-flame first nozzle 4 has a diameter of 4.5 mm, and the short-flame A-type first nozzle 4 has a diameter of 8.0 mm.

In addition, the medium-flame first nozzle 4 and the short-flame A-type first nozzle 4 have different diameters of the main ejection holes 43 (diameters of the circular holes in the cross section perpendicular to the axis P). is larger in the medium flame type first nozzle 4 .
Incidentally, as an example of the diameter of the main ejection hole 43, the medium-flame first nozzle 4 has a diameter of 15.0 mm, and the short-flame A-type first nozzle 4 has a diameter of 5.0 mm.

In this embodiment, the total cross-sectional area of all the secondary ejection holes 44 (hereinafter sometimes referred to as the total secondary ejection hole area) is the cross-sectional area of the main ejection holes 43 (hereinafter referred to as the main ejection hole area). (which may be the case) or greater than the primary orifice area. The cross-sectional area refers to the area of the cross section perpendicular to the axis Q of each of the main ejection hole 43 and the sub-ejection hole 44 .
Furthermore, in this embodiment, the ratio of the total area of the secondary ejection holes to the area of the main ejection holes (hereinafter sometimes referred to as the main and secondary ejection hole area ratio) is configured to be 1-21.
Incidentally, in one example of the diameter of the main ejection hole 43 and the number and diameter of the sub ejection holes 44 described above, the main and sub ejection hole area ratio of the medium flame type first nozzle 4 is about 1.1, and the short flame The A-type primary nozzle 4 is about 20.5.

Next, the short-flame B-type first nozzle 4 will be described with reference to FIGS. 8 to 10. FIG.
In the short-flame B-type first nozzle 4, an annular sub-ejection hole group 46 in which a plurality of sub-ejection holes 44 are arranged in a ring at the same location in the direction of the ejection path axis P when viewed in the ejection path axis P direction has a cylindrical shape. Annular secondary ejection hole groups 46 are provided at a plurality of locations in the direction of the ejection passage axis P on the peripheral wall 42w of the portion 42, and are provided in multiple stages in the direction of the ejection passage axis P on the peripheral wall 42w of the cylindrical portion 42. .
Incidentally, in this embodiment, the short-flame B-type first nozzle 4 is provided with the annular sub-jet hole groups 46 in two stages.
Here, of the two-stage annular sub-jet hole groups 46, the front one may be called a front-stage annular sub-jet hole group 46f, and the rear one may be called a rear-stage annular sub-jet hole group 46r.

Of the two-stage annular sub-jet hole group 46, the plurality of sub-jet holes 44 in the foremost front-stage annular sub-jet hole group 46f in the direction of the jet path axis P have tip openings 44a formed on the peripheral wall of the cylindrical portion 42. It is provided in a state of being opened at a portion corresponding to the front end surface 42s of the ejection passage axis P direction in the ejection passage 42w.
Furthermore, among the two-stage annular sub-jet hole groups 46, the axis Q of each of the plurality of sub-jet holes 44 in the front-stage annular sub-jet hole group 46f widens toward the front in the direction of the jet path axis P. It has a spiral shape that shifts in the same circumferential direction of the cylindrical portion 42 .
On the other hand, the axis Q of each of the plurality of sub-jet holes 44 in the rear-stage annular sub-jet hole group 46f has a shape that expands toward the end but does not have a swirling shape. It overlaps with P.

In the front annular sub-jet hole group 46f, 12 sub-jet holes 44 are arranged annularly at regular intervals when viewed in the direction of the jet passage axis P, and in the rear-stage annular sub-jet hole group 46r, 6 sub-jet holes 44 are arranged. The sub-ejection holes 44 are provided in a state of being annularly arranged at equal intervals when viewed in the direction of the ejection passage axis P.
The PCD of the sub-ejection hole arrangement circle C1 in the plurality of sub-ejection holes 44 of the front-stage annular sub-ejection hole group 46f that opens to the tip surface 42s of the peripheral wall 42w of the cylindrical portion 42 is the above-mentioned medium flame type and short flame A type. It has the same diameter as the first nozzle 4, and is 32 mm in this embodiment.

In both the front-stage annular sub-jet hole group 46f and the rear-stage annular sub-jet hole group 46r, the forward expansion angle α (see FIG. 8) of the axis Q of each of the plurality of sub-jet holes 44 is , and an example of the divergence angle α is 30°, for example.
The turning angle β (see FIG. 10) of the axis Q of each of the plurality of sub-ejection holes 44 of the front-stage annular sub-ejection hole group 46f is the same for all the sub-ejection holes 44, and an example of the turning angle β is For example, 15°.

All the sub-ejection holes 44 of the front-stage annular sub-ejection hole group 46f have the same diameter, and all the sub-ejection holes 44 of the rear-stage annular sub-ejection hole group 46r have the same diameter.
Incidentally, an example of the diameter of the sub-ejection holes 44 of the front-stage annular sub-ejection hole group 46f is 4.3 mmφ, and an example of the diameter of the sub-ejection holes 44 of the rear-stage annular sub-ejection hole group 46r is 6.0 mmφ. be.
An example of the diameter of the main ejection hole 43 is 10.0 mmφ.
In this case, the main and sub ejection hole area ratio of the short flame B-type first nozzle 4 is about 4.4.

As shown in FIGS. 1, 2 and 4, the second nozzle 5 includes a disk-shaped portion 53 having the same outer diameter as the large diameter portion 42b of the cylindrical portion 42 of the first nozzle 4, and a disk-shaped portion 53 having the same outer diameter as the large diameter portion 42b. A cylindrical portion 54 having a diameter smaller than that of the disk-shaped portion 53 and having a substantially cylindrical outer shape coaxially connected to the base end surface of the disk-shaped portion 53 .

In this embodiment, when viewed in the direction of the ejection path axis P, the plurality of liquid fuel ejection holes 51 are provided in the disk-shaped portion 53 of the second nozzle 5 in a state in which they are arranged in a ring. It is provided in the disk-shaped portion 53 of the second nozzle 5 in a state of being annularly arranged around the outer peripheral portion of the plurality of liquid fuel ejection holes 51 arranged annularly.
More specifically, a plurality of liquid fuel ejection holes 51 are provided in the disk-shaped portion 53 of the second nozzle 5 in an arrangement form in which the respective tip openings 51a are arranged annularly at equal intervals, and a plurality of gas fuel ejection holes 51 are provided. The disk-shaped portion 53 of the second nozzle 5 is arranged such that the tip openings 52a of the ejection holes 52 are arranged at equal intervals in a ring concentric with the circle in which the tip openings 51a of the plurality of liquid fuel ejection holes 51 are arranged. is provided in
In this embodiment, six gas fuel ejection holes 52 are provided and three liquid fuel ejection holes 51 are provided.

Here, in FIG. 4, a circle (hereafter referred to as a liquid fuel injection (sometimes referred to as a hole array circle) is denoted by reference numeral C2, and is formed by connecting the centers of the tip openings 52a of the six gas fuel ejection holes 52 that open to the tip surface of the disk-shaped portion 53 of the second nozzle 5. A circle (hereinafter sometimes referred to as a gas fuel injection hole array circle) is denoted by reference symbol C3.
Incidentally, the PCD of the liquid fuel ejection hole array C2 is 8 mm, and the PCD of the gas fuel ejection hole array C3 is 22 mm. This value is an example and can be changed as appropriate under the condition that the PCD of the gas fuel ejection hole array C3 is larger than the PCD of the liquid fuel ejection hole array C2.
Note that the tip opening 52a of the gas fuel ejection hole 52 and the tip opening 51a of the liquid fuel ejection hole 51 are provided at the same position in the gas flow direction.

As shown in FIGS. 1 and 4, the columnar portion 54 of the second nozzle 5 has a liquid fuel introduction hole for supplying the liquid fuel received from the double pipe member 2 (to be described later) to the three liquid fuel ejection holes 51. 55 is provided coaxially with the axis P of the second nozzle 5 in a state in which the base end openings of the three liquid fuel ejection holes 51 are included in the opening at the tip.
Further, the base end side portion of the liquid fuel introduction hole 55 is configured as a large diameter portion 55b having a larger diameter than the tip end side portion.

As shown in FIGS. 1 and 4 , the three liquid fuel ejection holes 51 are arranged in the disk-shaped portion 53 of the second nozzle 5 with their axes parallel to the axis P of the second nozzle 5 . is provided.
On the other hand, the six gas fuel ejection holes 52 are arranged such that the axial center approaches the axial center P of the second nozzle 5 toward the tip side, and is displaced in the same direction in the circumferential direction when viewed in the direction of the axial center P. It is provided on the disc-shaped portion 53 of the two nozzles 5 .
Here, as shown in FIG. 4, the tip openings 51a of the three liquid fuel ejection holes 51 are in phase with the tip openings 52a of the alternate gas fuel ejection holes 52 in the circumferential direction. It is provided on the disc-shaped portion 53 of the second nozzle 5 in an arrangement form.

As shown in FIG. 1, the disk-shaped portion 53 of the second nozzle 5 is coaxially brought into contact with the base end surface of the large-diameter portion 42b of the cylindrical portion 42 of the first nozzle 4. The tip openings 52 a of the six gas fuel ejection holes 52 provided in the portion 53 are configured to face the opening of the receiving portion 41 g in the ejection path 41 of the first nozzle 4 .

As shown in FIG. 1, the double tube member 2 is configured by integrally including an inner tube 21 and an outer tube 22 coaxially. The inner tube 21 has an outer diameter substantially equal to the inner diameter of the large diameter portion 55b on the base end side of the liquid fuel introduction hole 55 provided in the cylindrical portion 54 of the second nozzle 5. , the inner diameter of which is larger than the outer diameter of the cylindrical portion 54 of the second nozzle 5 .
A male threaded portion 23 is formed at the tip of the outer peripheral surface of the outer tube 22 of the double tube member 2 .
That is, in the double pipe member 2, the tip of the inner tube 21 is fitted into the large diameter portion 55b on the base end side of the liquid fuel introduction hole 55 of the second nozzle 5, and the tip of the outer tube 22 is the second nozzle. It is configured to be connectable to the base end of the second nozzle 5 while covering the base end portion of the cylindrical portion 54 of the two nozzles 5 .

The annular space between the inner peripheral surface of the outer tube 22 and the outer peripheral surface of the inner tube 21 is configured as a gas fuel supply path 24 for supplying gas fuel, and the inner space of the inner tube 21 is configured as a liquid for supplying liquid fuel. It is configured in the fuel supply path 25 .
That is, the liquid fuel supply path 25 is configured to communicate with the three liquid fuel ejection holes 51 via the liquid fuel introduction holes 55 .
Although illustration is omitted, a gas fuel supply port for supplying gas fuel to the gas fuel supply path 24 is provided at the proximal end of the double pipe member 2 so that the inner peripheral surface of the outer tube 22 and the outer peripheral surface of the inner tube 21 are provided. A liquid fuel supply port for supplying liquid fuel to the liquid fuel supply path 25 is provided in communication with the inner pipe 21 .

As shown in FIGS. 1 and 2, the water-cooling jacket 3 has a substantially cylindrical shape with a through-hole 31 penetrating in the direction of the axis P. A water-cooling jacket 3 for cooling water is provided in the peripheral wall portion thereof. A portion 32 is provided.
The through-hole 31 of the water-cooling jacket 3 has a small-diameter portion 31s on the tip end side, which has approximately the same diameter as the outer diameter of the cylindrical portion 42 of the first nozzle 4, and a large-diameter portion 42b of the cylindrical portion 42 of the first nozzle 4. It is composed of a large-diameter hole portion 31b on the proximal end side having a larger diameter than the outer diameter, and is configured in a two-stage shape having a stepped portion toward the proximal end side.
A female screw portion 33 is provided on the base end side of the inner peripheral surface of the large diameter hole portion 31 b of the through hole 31 of the water cooling jacket 3 .
Although not shown, the water cooling jacket 3 is provided with a water inlet pipe portion for supplying cooling water to the water flow portion 32 and a water outlet pipe portion for discharging the cooling water from the water flow portion 32. .

As shown in FIG. 1 , the cylindrical connecting member 6 has a two-step shape in which both the outer peripheral surface and the inner peripheral surface are smaller in diameter on the distal end side than on the proximal end side, and the inner peripheral surface is the diameter of the second nozzle 5 . It is configured to have a larger diameter than the cylindrical portion 54 . A male threaded portion 61 that can be screwed into the female threaded portion 33 of the inner peripheral surface of the large diameter hole portion 31b of the through hole 31 of the water cooling jacket 3 is formed at the tip of the outer peripheral surface of the cylindrical connecting member 6. A female threaded portion 62 that can be screwed into the male threaded portion 23 of the outer peripheral surface of the outer tube 22 of the double tube member 2 is formed at the proximal end portion of the inner peripheral surface of the cylindrical connecting member 6 .

As shown in FIGS. 1, 5 and 8, in order to assemble the respective members and manufacture the gas atomized burner, the first nozzle 4 is protruded from the tip of the water-cooling jacket 3, and is water-cooled. The second nozzle 5 is fitted in the through-hole 31 of the jacket 3 , and the second nozzle 5 is arranged with the distal end surface of the disc-shaped portion 53 abutting against the proximal end surface of the large-diameter portion 42 b of the cylindrical portion 42 of the first nozzle 4 .
By screwing the male threaded portion 61 at the distal end of the cylindrical connecting member 6 to the female threaded portion 33 at the proximal end of the water cooling jacket 3 , the cylindrical connecting member 6 is covered with the outer circumference of the second nozzle 5 . , to the proximal end of the water cooling jacket 3 . Furthermore, in a state in which the tip of the inner tube 21 of the double tube member 2 is fitted into the large diameter portion 55b of the liquid fuel introduction hole 55 of the second nozzle 5, the tip of the outer tube 22 of the double tube member 2 is The double pipe member 2 is connected to the proximal end of the cylindrical connecting member 6 by screwing the male threaded portion 23 into the female threaded portion 62 at the proximal end of the cylindrical connecting member 6 .

Then, the front side portion of the cylindrical portion 42 of the first nozzle 4 (the front side portion including the installation position of the rear annular sub-jet hole group 46r in the short-flame B-type first nozzle 4) reaches the tip of the water cooling jacket 3. and the tip surface of the large-diameter portion 42b of the cylindrical portion 42 of the first nozzle 4 is brought into contact with the step portion facing the base end of the inner peripheral surface of the through hole 31 of the water-cooling jacket 3, and the disc of the second nozzle 5 The distal end surface of the shaped portion 53 is abutted against the proximal end surface of the large diameter portion 42b of the cylindrical portion 42 of the first nozzle 4, and the distal end of the double tube member 2 is connected to the proximal end of the second nozzle 5 and the cylindrical portion. The water cooling jacket 3, the first nozzle 4, the second nozzle 5, the cylindrical connecting member 6 and the double pipe member 2 are integrally assembled while being connected to the proximal end of the member 6 to assemble the gas atomizing burner. .

1, 5 and 8 denotes an O-ring for sealing the fitting portion between the proximal end of the second nozzle 5 and the distal end of the inner pipe 21 of the double pipe member 2. As shown in FIG.

As shown in FIGS. 1, 5 and 8, in the gas atomizing burner assembled in this manner, the outer peripheral surface of the cylindrical portion 54 of the second nozzle 5 and the inner peripheral surface of the tubular connecting member 6 form The base end of the annular space communicates with the gas fuel supply passage 24 formed by the double pipe member 2, and the distal end communicates with the plurality of gas fuel ejection holes 52 of the second nozzle 5. , this annular space is configured to be used as a gas fuel introduction passage 63 that receives the gas fuel supplied to the gas fuel supply passage 24 and sends it to the plurality of gas fuel ejection holes 52 .

Although illustration is omitted, the liquid fuel is supplied to the liquid fuel supply path 25 from the liquid fuel supply port provided at the proximal end portion of the double pipe member 2, and the proximal end portion of the double pipe member 2 is supplied. Gas fuel is supplied to the gas fuel supply path 24 from the gas fuel supply port provided in the .

Then, as indicated by arrows in FIGS. 1, 5 and 8, the liquid fuel supplied to the liquid fuel supply passage 25 passes through the liquid fuel introduction hole 55 and flows into the three liquid fuels of the second nozzle 5. The gas fuel ejected from the ejection hole 51 to the receiving portion 41g of the ejection passage 41 of the first nozzle 4 and supplied to the gas fuel supply passage 24 passes through the gas fuel introduction passage 63 to the six nozzles of the second nozzle 5. is jetted from the gas fuel jet hole 52 to the receiving portion 41 g of the jet passage 41 of the first nozzle 4 .
The liquid fuel ejected from the three liquid fuel ejection holes 51 of the second nozzle 5 is atomized by the gas fuel ejected from the six gas fuel ejection holes 52 of the second nozzle 5, and the The atomized liquid fuel and the gas fuel are mixed in the receiving part 41g, and further mixed while flowing through the ejection passage 41, resulting in a mixture of the atomized liquid fuel and the gas fuel. The mixed fuel is ejected from the main ejection hole 43 and the plurality of sub ejection holes 44 to form a flame F and burn.

Furthermore, the combustion mode of medium-, short-flame, A-, and B-type gas atomizing burners equipped with medium-, short-flame, A-, and B-type gas atomizing burner nozzles 1 will be described in detail. do.
First, based on FIG. 1 and FIG. 5, the combustion modes of the medium flame type gas atomizing burner and the short flame type A gas atomizing burner will be described in detail.
In each of the medium flame type gas atomizing burner and the short flame A type gas atomizing burner, part of the atomized mixed fuel flowing through the ejection passage 41 is ejected from the main ejection hole 43 in the direction of the axis P of the ejection passage 41, and flows through the ejection passage 41. The remaining amount of the flowing atomized mixed fuel is jetted from a plurality of sub-jet holes 44 annularly arranged around the main jet hole 43 in a widening and swirling manner, and is jetted from the main jet hole 43 to be atomized. The mixed fuel and the atomized mixed fuel ejected from the plurality of secondary ejection holes 44 are combusted in the furnace.

The atomized mixed fuel is ejected from the plurality of sub-ejection holes 44 in a widening and swirling manner, so that the ejected atomized mixed fuel flows in a widening manner while swirling, preventing excessive diffusion. Since it is suppressed, the formed flame shape is stabilized.

Then, the cross-sectional area of the main injection hole 43, the number of the secondary injection holes 44, and the The length and thickness of the flame F formed in the furnace can be varied by setting the cross-sectional area of each of the plurality of sub-ejection holes 44 and the divergent angle of the axial center Q of each of the plurality of sub-ejection holes 44. It is possible to adjust the thickness.
That is, the temperature distribution formed in the furnace can be adjusted by adjusting the length and thickness of the flame F formed in the furnace.

Next, with reference to FIG. 8, the combustion mode of the short-flame B-type gas atomizing burner equipped with the short-flame B-type gas atomizing burner nozzle 1 will be described in detail.
In the short-flame B-type gas atomizing burner, part of the atomized mixed fuel flowing through the ejection passage 41 is ejected from the main ejection hole 43 in the direction of the axis P of the ejection passage 41, and atomized through the ejection passage 41. The remaining amount of the mixed fuel is ejected from the plurality of annularly arranged sub-ejection holes 44 of each of the two-stage annular sub-ejection hole groups 46 in a widening manner around the atomized mixed fuel ejected from the main ejection hole 43. be. Then, the atomized mixed fuel ejected from the main ejection hole 43 and the atomized mixed fuel ejected from the plurality of secondary ejection holes 44 of the two-stage annular secondary ejection hole group 46 are combusted in the furnace.

By the way, the atomized mixed fuel is jetted in a swirling manner in a divergent manner from the plurality of sub-ejection holes 44 of the first-stage annular sub-ejection hole group 46, so that the jetted atomized mixed fuel is swirled. Since the flame spreads out at the same time and excessive diffusion is suppressed, the shape of the formed flame is stabilized.

That is, the cross-sectional area of the main ejection hole 43, which is related to the ratio of the atomized mixed fuel ejected from the main ejection hole 43 and the atomized mixed fuel ejected from the multistage annular sub-ejection hole group 46, the ejection path axis The number of stages of the annular secondary ejection hole groups 46 arranged in the P direction, the number of the secondary ejection holes 44 of each annular secondary ejection hole group 46, the cross-sectional area of each of the plurality of secondary ejection holes 44 of each annular secondary ejection hole group 46, and each The length and thickness of the flame F formed in the furnace can be adjusted by variously setting the diverging angle of each of the plurality of secondary ejection holes 44 of the annular secondary ejection hole group 46 .
In particular, in the short-flame B-type gas atomizing burner nozzle 1, the annular secondary ejection hole group 46 is provided in a plurality of stages (in this embodiment, two stages) in the direction of the ejection passage axis P, so that it is formed in the furnace. This is effective in making the shape of the flame F relatively short and thick.

In order to evaluate that the temperature distribution formed in the furnace can be adjusted by adjusting the length and thickness of the flame F formed in the furnace by the gas atomizing burner nozzle 1 according to the present invention, evaluation was performed. conducted the test.
The results of the evaluation test are described below.
In the evaluation test, a gas atomizing burner equipped with each of the three types of gas atomizing burner nozzles 1 according to the present invention and the conventional gas atomizing burner nozzle 1 was installed in a test furnace and burned under the following test conditions. The temperature distribution formed inside was evaluated.

The test conditions were a gas fuel flow rate of 240 m ³ /h, a liquid fuel flow rate of 560 L/h, and an air ratio of 1.2. .
Then, in the test furnace, 6 thermocouples were provided at a distance of 1 m from the gas atomizing burner at intervals of 2 m. , the temperature distribution was measured.
Here, the liquid fuel used in the evaluation test is LSA heavy oil, and the gas fuel is town gas 13A.

FIG. 11 shows the results of the evaluation test.
As shown in FIG. 11, in the temperature distribution formed in the furnace, the position of the maximum temperature region is the position where the conventional gas atomizing burner is farthest from the gas atomizing burner, and the medium flame type gas atomizing burner and the short flame A type are at the maximum temperature region. The gas atomizing burners are positioned closer to the gas atomizing burners in order, and the short-flame B-type gas atomizing burner is the closest.

That is, the length of the formed flame F becomes shorter in the order of the conventional gas atomizing burner, the medium flame type gas atomizing burner, the short flame A type gas atomizing burner, and the end flame B type gas atomizing burner. It is considered that the thickness of the flame F that is generated is thickened.

[Another embodiment]
(A) Another embodiment will be described below for a case in which a plurality of secondary ejection holes 44 are arranged in a single row as viewed in the direction of the ejection path axis P, such as the first nozzle 4 of medium flame type or short flame A type. listed in
(A-1) The cross-sectional area of the main ejection hole 43, the number of the sub-ejection holes 44, the cross-sectional area of each of the plurality of sub-ejection holes 44, the divergence angle α of each axis Q, and the turning angle β are set as desired. Various changes are possible according to the temperature distribution in the furnace.
Incidentally, by changing the cross-sectional area of the main ejection hole 43, the number of the sub-ejection holes 44, and the cross-sectional area of each of the plurality of sub-ejection holes 44, even if the ratio of the main and sub-ejection hole areas is changed, the flame formed In order to shorten the flame, it is preferable to change the main and sub ejection hole area ratio in the range of 1 to 21.

(A-2) In the above-described embodiment, the plurality of secondary ejection holes 44 are provided so that the tip openings 44a thereof open to the portion corresponding to the tip surface 42s of the peripheral wall 42w of the cylindrical portion 42. Each tip opening 44a may be provided in a state of opening to a portion corresponding to the side peripheral surface of the peripheral wall 42w of the cylindrical portion 42. As shown in FIG.

(A-3) In the above-described embodiment, the axis Q of each of the plurality of sub-jet holes 44 is tapered and swirled. In a state where it overlaps with the axis P of the cylindrical portion 42, the tip may be flared.

(A-4) In the above-described embodiment, the cross-sectional areas of the plurality of sub-ejection holes 44, the spreading angles α of the axes Q, and the turning angles β of the axes Q are the same. Each cross-sectional area may be made different, each axial center Q may have different expansion angles α, and each axial center Q may have different turning angles β.

(B) Other embodiments of the case where the annular sub-jet hole groups 46 are provided in a plurality of stages like the short-flame B-type first nozzle 4 will be listed below.
(B-1) The number of stages of the annular secondary ejection hole group 46 is not limited to two stages as in the above embodiment, but can be changed in various ways according to the target temperature distribution in the furnace.

(B-2) The cross-sectional area of the main ejection hole 43, the number of the sub-ejection holes 44 in each stage of the annular sub-ejection hole group 46, and the cross-sectional area of each of the plurality of sub-ejection holes 44 in each stage of the annular sub-ejection hole group 46 , the divergence angle α and the turning angle β of the axis Q of each of the plurality of secondary ejection holes 44 in the annular secondary ejection hole group 46 of each stage can be varied in accordance with the desired temperature distribution in the furnace. .

(B- 3 ) In the above embodiment, in the plurality of sub-jet holes 44 in each stage of the annular sub-jet hole group 46, each cross-sectional area, each axial center Q diverging angle α, each axial center Q are the same, but it is also possible to make the respective cross-sectional areas different, make the respective axial centers Q diverge at different angles α, or make the respective axial centers Q have different turning angles β.

(C) In the above embodiment, the main ejection hole forming body 45 that closes the tip opening of the cylindrical portion 42 is provided, and the main ejection hole forming body 45 is formed with the main ejection holes 43. However, the main ejection hole forming body The tip opening of the cylindrical portion 42 may be used as the main ejection hole 43 without providing the 45 .

(D) In the above embodiment, the main/sub ejection hole area ratio is set to 1 or more, but it may be set to be smaller than 1.

The configurations disclosed in the above embodiments (including other embodiments, the same shall apply hereinafter) can be applied in combination with configurations disclosed in other embodiments unless there is a contradiction. The embodiments disclosed in this specification are examples, and the embodiments of the present invention are not limited thereto, and can be modified as appropriate without departing from the scope of the present invention.

As described above, it is possible to provide a gas atomizing burner nozzle capable of setting the temperature distribution in the furnace to a predetermined temperature distribution.

1 gas atomizing burner nozzle 4 first nozzle (first nozzle section)
5 Second nozzle (second nozzle part)
41 Ejection passage 42 Cylindrical portion 42s Tip surface 42w Peripheral wall 43 Main ejection hole 44 Sub-ejection hole 44a Tip opening 45 Main ejection hole formation body 46 Annular secondary ejection hole group 51 Liquid fuel ejection hole 52 Gas fuel ejection hole P Axis of ejection passage Center Q Axial center of sub-spout hole

Claims (5)

It has a cylindrical part inside which is a jet path through which the atomized mixed fuel in which the atomized liquid fuel and the gas fuel are mixed flows, and at the tip of the jet path, the atomized mixture that flows through the jet path a first nozzle section provided with a main ejection hole for ejecting fuel in the axial direction of the ejection passage;
A liquid fuel ejection hole for ejecting liquid fuel to the base end of the ejection passage, and a gas fuel for spraying gas fuel for atomizing the liquid fuel ejected from the liquid fuel ejection hole to the base end of the ejection passage. A gas atomizing burner nozzle comprising a second nozzle portion provided with a jet hole,
A plurality of sub-ejection holes communicating with the ejection path are provided in the peripheral wall of the cylindrical portion of the first nozzle part in a state of being arranged in a ring when viewed in the direction of the ejection path axis along the axis of the ejection path,
the axial center of each of the plurality of secondary ejection holes is tapered such that the axial center of each of the plurality of secondary ejection holes moves away from the axial center of the ejection path in the radial direction of the cylindrical portion toward the front in the axial direction of the ejection path;
An annular sub-ejection hole group in which a plurality of the sub-ejection holes are arranged annularly when viewed in the ejection path axis direction at the same location in the ejection path axis direction is formed in a plurality of the ejection path axis directions on the peripheral wall of the cylindrical portion. the annular secondary ejection hole group is provided in a plurality of stages in the axial direction of the ejection path on the peripheral wall of the cylindrical portion,
Of the plurality of stages of the annular sub-jet hole group, the plurality of sub-jet holes in the foremost annular sub-jet hole group in the jet path axial direction have tip openings that are located on the peripheral wall of the cylindrical portion. is provided in a state of opening in a portion corresponding to the front end surface facing forward in the axial direction of the ejection passage,
The axial centers of the plurality of secondary ejection holes in the foremost annular secondary ejection hole group in the direction of the axial center of the ejection path are arranged in a circular shape in which the axial centers of the plurality of secondary ejection holes are displaced in the same direction in the circumferential direction of the cylindrical portion toward the front in the direction of the axis of the ejection path. and
The axial centers of the plurality of sub-jet holes in the annular sub-jet hole group other than the foremost annular sub-jet hole group in the direction of the jet passage axis are in the cylindrical shape when viewed in the radial direction of the cylindrical portion. A gas atomizing burner nozzle that overlaps the axis of the part . A main ejection hole forming body is provided in a state in which the tip opening of the cylindrical portion is closed,
2. The gas atomizing burner nozzle according to claim 1 , wherein said main ejection hole is formed in said main ejection hole formation body so that the cross-sectional area thereof is smaller than the cross-sectional area of said ejection passage. 3. The method according to claim 2 , wherein a total secondary ejection hole area, which is the sum of the cross-sectional areas of all the secondary ejection holes, is equal to or larger than the main ejection hole area, which is the cross-sectional area of the main ejection holes. Gas atomized burner nozzle. 4. The gas atomizing burner nozzle according to claim 3 , wherein the ratio of the total sub-jet hole area to the main jet hole area is 1-21. A plurality of the liquid fuel ejection holes are arranged in an annular shape when viewed in the direction of the ejection passage axis,
5. The gas atomizing burner nozzle according to any one of claims 1 to 4, wherein a plurality of said gas fuel ejection holes are provided in a state of being arranged in a ring around the outer periphery of said plurality of liquid fuel ejection holes arranged in a ring.

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