JP6629619B2 - Burner chips, dual fluid burners and boilers - Google Patents

Description

  The present disclosure relates to burner chips, dual fluid burners, and boilers.

  2. Description of the Related Art In general, a two-fluid burner that atomizes liquid fuel by using energy of a spray medium is known. In a two-fluid burner, it is important to reduce the particle size of the atomized liquid fuel in order to reduce dust and NOx.

  As one of the two-fluid burners, there is an internal mixing type two-fluid burner in which a mixing chamber is provided inside a burner chip. In the internal mixing type two-fluid burner, the liquid fuel and the spray medium are mixed in advance in a mixing chamber inside the burner chip, and are jetted into a combustion space.

  For example, Patent Literatures 1 and 2 describe an internal mixing type two-fluid burner in which a mixing chamber is provided inside a burner chip. Further, in Patent Document 2, an injection hole for injecting atomized liquid fuel into a combustion chamber, a fuel supply passage connected to a fuel supply pipe, and a steam supply pipe are connected to a mixing chamber inside a burner chip. A configuration in which a steam supply passage is provided is also described.

JP 2003-172505 A JP-A-2015-64131

By the way, in the internal mixing type two-fluid burners described in Patent Literatures 1 and 2, there is a problem that the liquid fuel is not properly atomized due to poor flow of the liquid fuel inside the mixing chamber.
The present inventors have investigated the cause in more detail, and found that due to poor flow of the liquid fuel inside the mixing chamber, the thickness of the liquid film of the liquid fuel formed in the ejection hole becomes non-uniform. It was found that this is one of the causes of the inhibition. That is, in the two-fluid burner, usually, the liquid fuel supplied into the mixing chamber is mixed with the spray medium, and then is injected into the combustion space through the ejection hole. At this time, a liquid film is formed on the wall surface of the ejection hole by the liquid fuel. This liquid film is diffused into the combustion space by the fluid energy of the spray medium. However, due to the flow energy of the spray medium supplied into the mixing chamber, the flow of the liquid fuel is biased, and the thickness of the liquid film formed on the inner wall surface of the ejection hole becomes non-uniform in the circumferential direction. A thick part may hinder atomization. For this reason, a situation occurs in which the liquid fuel is not properly atomized.

  In view of the above circumstances, at least some embodiments of the present invention aim to provide a burner chip, a two-fluid burner, and a boiler that can appropriately atomize liquid fuel.

(1) A burner chip of a combustor according to at least some embodiments of the present invention includes:
A fuel chamber into which liquid fuel is introduced, and a chip body having at least one ejection hole for spraying the liquid fuel from the fuel chamber;
At least one medium supply pipe for guiding a spray medium to the ejection hole,
With
In the upstream region of the ejection hole, the medium supply pipe is inserted into the ejection hole,
In the upstream region of the ejection hole, a gap communicating with the fuel chamber is formed between the medium supply tube and the ejection hole in a radial direction of the medium supply tube ,
When the insertion length of the medium supply pipe into the ejection hole is L, and the size of the gap between the medium supply pipe and the ejection hole is d, the relationship of 5 ≦ L / d ≦ 20 is satisfied. Fill ,
The chip body,
A fuel inlet for introducing the liquid fuel into the fuel chamber from the outer peripheral side of the tip body;
A medium inlet for introducing the spray medium into the medium supply pipe from the rear end side of the tip body,
Including
The medium supply pipe extends in the fuel chamber from the rear end side of the tip body toward the ejection hole .
In the burner chip of the above (1), a medium supply pipe is inserted in an upstream region of the ejection hole, and communicates with the fuel chamber between the medium supply pipe and the ejection hole in a radial direction of the medium supply pipe. A gap is formed.
As described above, the liquid fuel is supplied to the ejection holes from the fuel chamber through the radial gap between the medium supply pipe and the ejection holes. A liquid fuel liquid film having a relatively uniform film thickness can be formed on the inner wall surface. Therefore, unlike the case where the spray medium is directly introduced into the fuel chamber, a situation in which the liquid film of the liquid fuel on the inner wall surface of the ejection hole becomes locally thick can be avoided, and the liquid film is formed uniformly and thinly. be able to. Thereby, the liquid film can be appropriately diffused by the fluid energy of the spray medium supplied to the upstream side of the ejection hole, and the atomization of the liquid fuel can be promoted.
Further, according to the above configuration (1), L / d is set to 5 in a relationship between the insertion length L of the medium supply pipe into the ejection hole and the size d of the gap between the medium supply pipe and the ejection hole. By setting the above, to ensure a sufficient length of the gap between the outer peripheral surface of the medium supply pipe and the inner wall surface of the ejection hole, to develop a boundary layer of the flow of the liquid fuel passing through the gap, The liquid fuel having a thin liquid film can flow along the inner wall surface of the ejection hole on the downstream side of the gap. Further, since the size d of the gap is sufficiently reduced with respect to the insertion length L, the liquid film thickness of the liquid fuel can be reduced also for this reason. On the other hand, by setting L / d to 20 or less, an increase in pressure loss due to the gap between the medium supply pipe and the ejection hole can be suppressed.
Liquid fuel from the fuel chamber flows through a radial gap between the outer peripheral surface of the medium supply pipe and the inner wall surface of the ejection hole in an upstream region of the ejection hole. In this regard, in the configuration of the above (1), the medium supply pipe extends from the rear end side of the chip body toward the ejection hole in the fuel chamber, and the liquid supply pipe surrounds the medium supply pipe in the fuel chamber. Since the fuel flows, the flow of the liquid fuel toward the radial gap in the upstream region of the ejection hole is not obstructed by the medium supply pipe.

(2) The burner chip of the combustor according to at least some embodiments of the present invention includes:
A fuel chamber into which liquid fuel is introduced, and a chip body having at least one ejection hole for spraying the liquid fuel from the fuel chamber;
At least one medium supply pipe for guiding a spray medium to the ejection hole,
With
In the upstream region of the ejection hole, the medium supply pipe is inserted into the ejection hole,
In the upstream region of the ejection hole, a gap communicating with the fuel chamber is formed between the medium supply tube and the ejection hole in a radial direction of the medium supply tube,
When the insertion length of the medium supply pipe into the ejection hole is L, and the size of the gap between the medium supply pipe and the ejection hole is d, the relationship of 5 ≦ L / d ≦ 20 is satisfied. Fill,
The chip body has a plurality of the ejection holes respectively provided at different positions in the axial direction of the chip body,
A plurality of the medium supply pipes are respectively inserted into the plurality of ejection holes in the upstream region of the ejection hole,
The plurality of medium supply pipes extend along the axial direction of the chip main body, and are connected to a medium collecting channel for guiding the spray medium to the plurality of medium supply pipes.
According to the above configuration (2), atomized liquid fuel can be injected over a wide range in the axial direction of the burner chip, and the mixing state of atomized liquid fuel and combustion air can be improved. Combustibility can be improved. Further, since the medium supply pipe is inserted in the upstream region of each ejection hole, atomization of the liquid fuel is promoted for the reason described in the above (1), and the combustibility can be effectively improved.

( 3 ) In some embodiments, in the configuration of the above (1) or 2 ,
The medium supply pipe is inserted into the ejection hole only in the upstream region of the ejection hole such that a tip end of the medium supply pipe is located between an upstream end and a downstream end of the ejection hole. ,
In the downstream region of the ejection hole, the liquid fuel supplied from the fuel chamber through the gap and the spray medium supplied from the medium supply pipe are mixed.

According to the configuration of the above ( 3 ), the liquid fuel having a relatively thin liquid film and the spray medium are mixed in the downstream region of the ejection hole in which the medium supply pipe is not provided, so that the liquid fuel can be effectively removed. It can be atomized.

( 4 ) In some embodiments, in any one of the above configurations (1) to (3) ,
The gap is an annular gap formed between an inner wall surface of the ejection hole and an outer peripheral surface of the medium supply pipe.

According to the above configuration ( 4 ), an annular gap is formed between the inner wall surface of the ejection hole and the outer peripheral surface of the medium supply pipe. An annular liquid film can be formed. Therefore, the liquid fuel can be effectively atomized.

( 5 ) In some embodiments, in any one of the above (1) to ( 4 ),
The chip body has a plurality of the ejection holes respectively provided at different positions in a circumferential direction of the chip body,
The plurality of medium supply pipes are respectively inserted into the plurality of ejection holes in the upstream region of the ejection hole.

According to the above configuration ( 5 ), atomized liquid fuel can be injected over a wide range in the circumferential direction of the burner tip, and the mixing state of atomized liquid fuel and combustion air can be improved. Combustibility can be improved. Further, since the medium supply pipe is inserted in the upstream region of each ejection hole, atomization of the liquid fuel is promoted for the reason described in the above (1), and the combustibility can be effectively improved.

( 6 ) A two-fluid burner according to at least some embodiments of the present invention includes:
A burner chip according to any one of the above (1) to ( 5 ),
A burner body configured to hold the burner tip on the tip side, and to supply the liquid fuel and the spray medium toward the burner tip.
Is provided.

According to the two-fluid burner of the above ( 7 ), the burner chip is capable of appropriately diffusing the liquid film of the liquid fuel by the fluid energy of the spray medium supplied to the upstream side of the ejection hole, and promoting the atomization of the liquid fuel. Therefore, a two-fluid burner capable of reducing dust and NOx can be provided.

( 7 ) A boiler according to at least some embodiments of the present invention includes:
A two-fluid burner according to the above ( 7 ),
A furnace that forms a combustion space in which the liquid fuel injected from the two-fluid burner burns;
Is provided.

According to the boiler of ( 7 ), a two-fluid burner capable of reducing soot and NOx is provided, so that a highly reliable boiler can be provided.

  According to at least some embodiments of the present invention, it is possible to uniformly thin the liquid film of the liquid fuel formed on the inner wall surface of the ejection hole, so that the fluid of the spray medium supplied to the upstream side of the ejection hole is provided. The liquid film can be appropriately diffused by the energy, and the atomization of the liquid fuel can be promoted.

It is sectional drawing along the axial direction of the two-fluid burner which concerns on one Embodiment. FIG. 2 is a front view of the burner chip in one embodiment (a view taken along the line AA in FIG. 1). It is sectional drawing (BB sectional drawing of FIG. 1) of the burner chip in one Embodiment. It is a fragmentary sectional view along the axial direction of the two-fluid burner concerning one embodiment. It is sectional drawing along the axial direction of the two-fluid burner which concerns on other embodiment. It is sectional drawing along the axial direction of the two-fluid burner which concerns on another embodiment. It is a figure which shows typically the flow velocity distribution of the liquid fuel in the clearance gap between the medium supply pipe of a burner chip, and an ejection hole. It is a lineblock diagram of a boiler concerning one embodiment.

  Hereinafter, some embodiments of the present invention will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in the embodiments or shown in the drawings are not intended to limit the scope of the present invention thereto, but are merely illustrative examples. Absent.

  By exemplifying FIG. 1, an overall configuration of a two-fluid burner 1 according to some embodiments will be schematically described. FIG. 1 is a sectional view along an axial direction of a two-fluid burner 1 according to one embodiment. In the present embodiment, the axial direction is a direction along the central axis O of the two-fluid burner 1 or the burner chip 10.

  A two-fluid burner 1 according to some embodiments includes a burner main body 2 and a burner tip 10 held at a tip of the burner main body 2.

The burner main body 2 is configured to hold the burner chip 10 on the distal end side and supply the liquid fuel F and the spray medium S to the burner chip 10.
For example, the burner main body 2 includes a liquid fuel pipe 3 for supplying the liquid fuel F toward the burner chip 10 and a spray medium pipe 4 for supplying the spray medium S toward the burner chip 10. Prepare.
A burner chip 10 is detachably attached to the burner main body 2 including the liquid fuel pipe 3 and the spray medium pipe 4 by a fastening ring 9.
The liquid fuel pipe 3 communicates with the fuel chamber 12 of the burner chip 10 via a fuel inlet 13. The spray medium pipe 4 communicates with the medium supply pipe 16 of the burner chip 10 via a medium inlet 17. The liquid fuel pipe 3 or the spray medium pipe 4 may be provided along the axial direction.

Next, a specific configuration of the burner chip 10 will be described with reference to FIGS.
FIG. 2A is a front view of the burner chip 10 in one embodiment (a view taken along the line AA in FIG. 1). FIG. 2B is a cross-sectional view (a cross-sectional view taken along the line BB of FIG. 1) of the burner chip 10 according to the embodiment. FIG. 3 is a partial cross-sectional view along the axial direction of the two-fluid burner 1 according to one embodiment. FIG. 4 is a sectional view along an axial direction of a two-fluid burner 1 according to another embodiment. FIG. 5 is a cross-sectional view along the axial direction of a two-fluid burner 1 according to still another embodiment.
In addition, in FIGS. 3 to 5 described below, the burner main body 2 exemplifies the same configuration as that of FIG. 1 described above, but the configuration of the burner main body 2 is not limited to this.

As illustrated in FIGS. 1 to 5, a burner chip 10 according to some embodiments includes a fuel chamber 12 into which the liquid fuel F is introduced, and at least a liquid fuel F from the fuel chamber 12. The apparatus includes a tip body 11 having one ejection hole 14 and at least one medium supply pipe 16 for guiding the spray medium S to the ejection hole 14.
The medium supply pipe 16 is inserted into the ejection hole 14 in an upstream region 14 a of the ejection hole 14.
In the upstream area 14 a of the ejection hole 14, a gap 20 communicating with the fuel chamber 12 is formed between the medium supply pipe 16 and the ejection hole 14 in the radial direction of the medium supply pipe 16.
For example, the gap 20 is an annular gap formed by the inner wall surface 14 e of the ejection hole 14 and the outer peripheral surface 16 a of the medium supply pipe 16.

In the configuration example shown in FIG. 1, the fuel chamber 12 is formed in an annular shape around the central axis O of the burner chip 10. On the other hand, in the configuration example shown in FIG. 3, the fuel chamber 12 is formed in a tubular shape around the central axis O of the burner chip 10.
In the medium supply pipe 16, a region provided in the fuel chamber 12 is provided along the extending direction of the fuel chamber 12, and a region provided in the ejection hole 14 is provided along the extending direction of the ejection hole 14. You may be.

As described above, since the liquid fuel F is supplied from the fuel chamber 12 to the ejection holes 14 through the radial gap 20 between the medium supply pipe 16 and the ejection holes 14, the influence of the flow of the spray medium S is reduced. A liquid film of the liquid fuel F having a relatively uniform film thickness can be formed on the inner wall surface 14e of the ejection hole 14 while suppressing this. Therefore, unlike the case where the spray medium S is directly introduced into the fuel chamber 12, it is possible to avoid a situation where the liquid film of the liquid fuel F on the inner wall surface 14e of the ejection hole 14 becomes locally thick, and the liquid film can be made uniform. It can be formed as thin as possible. Thereby, the liquid film can be appropriately diffused by the fluid energy of the spray medium S supplied to the upstream side of the ejection hole 14, and the atomization of the liquid fuel F can be promoted.
Further, an annular gap 20 is formed between the inner wall surface 14 e of the ejection hole 14 and the outer peripheral surface 16 a of the medium supply pipe 16. An annular liquid film can be formed. Therefore, the liquid fuel F can be effectively atomized.

Further, the medium supply pipe 16 is provided only in the upstream region 14a of the ejection hole 14 so that the tip portion 16b of the medium supply pipe 16 is located between the upstream end 14a1 and the downstream end 14b1 of the ejection hole 14. 14 may be inserted.
In this case, the liquid fuel F supplied from the fuel chamber 12 through the gap 20 and the spray medium S supplied from the medium supply pipe 16 are mixed in the downstream region 14 b of the ejection hole 14. You.

  According to the above configuration, the liquid fuel F having a relatively thin liquid film and the spray medium S are mixed in the downstream region 14b of the ejection hole 14 where the medium supply pipe 16 is not provided, so that the liquid fuel F is effectively used. It can be finely divided.

In the embodiment illustrated in FIGS. 1, 2A and 2B, the chip body 11 has a plurality of ejection holes 14 provided at different positions in the circumferential direction of the chip body 11, respectively. For example, in the configuration illustrated in FIG. 2, eight ejection holes 14 are provided in the chip body 11 at equal intervals in the circumferential direction.
In this case, the plurality of medium supply pipes 16 are inserted into the plurality of ejection holes 14 in the upstream region 14a of the ejection hole 14, respectively.

  According to the above configuration, the atomized liquid fuel F can be injected over a wide range in the circumferential direction of the burner chip 10, and the combustion state is improved by improving the mixing state of the atomized liquid fuel F and the combustion air. Performance can be improved. Further, since the medium supply pipe 16 is inserted in the upstream area 14a of each of the ejection holes 14, atomization of the liquid fuel F is promoted for the above-described reason, and the combustibility can be effectively improved.

  As illustrated in FIG. 3, in the above-described burner chip 10, the insertion length of the medium supply pipe 16 into the ejection hole 14 is L, and the size of the gap between the medium supply pipe 16 and the ejection hole 14 is d. In this case, the relationship of 5 ≦ L / d ≦ 20 may be satisfied.

Here, a flow phenomenon of the liquid fuel in the gap 20 between the medium supply pipe 16 of the burner chip 10 and the ejection hole 14 will be described with reference to FIG. FIG. 6 is a diagram schematically showing a flow velocity distribution of the liquid fuel F in the gap 20 between the medium supply pipe 16 of the burner chip 10 and the ejection hole 14. In this figure, a case where at least a part of the entrance 20a of the gap 20 is spread in a bell mouth shape toward the downstream side will be described as an example for easy understanding.
As shown in FIG. 6, the liquid fuel F (fluid) flowing in the gap 20 between the inner wall surface 14 e of the ejection hole 14 and the outer peripheral surface 16 a of the medium supply pipe 16 has no boundary layer at the entrance 20 a of the gap 20. Due to its development, it has a uniform flow velocity distribution in the width direction. Here, the width direction corresponds to the radial direction R of the tip end portion 16b of the medium supply pipe 16.
The boundary layer develops toward the downstream side from the entrance 20a of the gap 20, and the boundary layer is stabilized at a certain distance from the entrance 20a toward the downstream side with respect to the size d of the gap.

According to the above configuration, L / d is set to 5 or more in the relationship between the insertion length L of the medium supply pipe 16 into the ejection hole 14 and the size d of the gap 20 between the medium supply pipe 16 and the ejection hole 14. In this case, the length of the gap 20 between the outer peripheral surface 16a of the medium supply pipe 16 and the inner wall surface 14e of the ejection hole 14 is sufficiently ensured, and the flow of the liquid fuel F passing through the gap 20 is controlled. By developing the boundary layer, the liquid fuel F having a thin liquid film can flow along the inner wall surface 14e of the ejection hole 14 on the downstream side of the gap 20.
Further, since the size d of the gap 20 is sufficiently reduced with respect to the insertion length L, the liquid film thickness of the liquid fuel F can be reduced for this reason as well.
On the other hand, by setting L / d to 20 or less, an increase in pressure loss due to the gap 20 between the medium supply pipe 16 and the ejection hole 14 can be suppressed.

In the embodiments illustrated in FIGS. 1, 4 and 5, the tip body 11 includes a fuel inlet 13 for introducing the liquid fuel F into the fuel chamber 12 from the outer peripheral side of the tip body 11, and a tip body 11. And a medium inlet 17 for introducing the spray medium S into the medium supply pipe 16 from the rear end side.
In this configuration, the medium supply pipe 16 extends in the fuel chamber 12 from the rear end side of the tip body 11 toward the ejection hole 14.

The liquid fuel F from the fuel chamber 12 flows through the radial gap 20 between the outer peripheral surface 16a of the medium supply pipe 16 and the inner wall surface 14e of the ejection hole 14 in the upstream region 14a of the ejection hole 14. In this regard, in the above-described configuration, the medium supply pipe 16 extends from the rear end side of the chip body 11 toward the ejection hole 14 in the fuel chamber 12, and the medium supply pipe 16 Since the liquid fuel F flows around the periphery, the flow of the liquid fuel F toward the radial gap 20 in the upstream region 14 a of the ejection hole 14 is not obstructed by the medium supply pipe 16.
Therefore, according to the above configuration, the liquid fuel F and the spray medium S in the fuel chamber 12 are different from the case where the medium supply pipe 16 is connected to a medium inlet (not shown) provided on the outer peripheral side of the chip body 11. Can be simplified.

In the embodiment illustrated in FIG. 5, the chip body 11 has a plurality of ejection holes 14 provided at different positions in the axial direction of the chip body 11, respectively.
The plurality of medium supply pipes 16 are inserted into the plurality of ejection holes 14 in the upstream region 14a of the ejection hole 14, respectively. The plurality of medium supply pipes 16 extend along the axial direction of the chip main body 11, and communicate with a medium collecting flow path 19 for guiding the spray medium S to the plurality of medium supply pipes 16.

  According to the above configuration, the atomized liquid fuel F can be injected over a wide range in the axial direction of the burner chip 10, and the mixing state of the atomized liquid fuel F and the combustion air is improved for combustion. Performance can be improved. Further, since the medium supply pipe 16 is inserted in the upstream area 14a of each of the ejection holes 14, atomization of the liquid fuel F is promoted for the above-described reason, and the combustibility can be effectively improved.

Also, in the embodiment illustrated in FIG. 5, the chip body 11 may include a plurality of ejection holes 14 provided at different positions in the circumferential direction of the chip body 11 (see FIG. 2A).
In this case, the plurality of medium supply pipes 16 are respectively inserted into the plurality of ejection holes 14 in the upstream region 14 a of the ejection hole 14.

  According to the above configuration, the atomized liquid fuel F can be injected over a wide range in the circumferential direction of the burner chip 10, and the combustion state is improved by improving the mixing state of the atomized liquid fuel F and the combustion air. Performance can be improved. Further, since the medium supply pipe 16 is inserted in the upstream area 14a of each of the ejection holes 14, atomization of the liquid fuel F is promoted for the above-described reason, and the combustibility can be effectively improved.

  Next, a boiler 50 which is an example of an application destination of the above-described two-fluid burner 1 will be described with reference to FIG. However, the application destination of the two-fluid burner 1 described above is not limited to the boiler 50, and can be used in other combustion devices.

  A boiler 50 according to some embodiments includes the above-described two-fluid burner 1 and a furnace 52 that forms a combustion space 100 in which the liquid fuel F injected from the two-fluid burner 1 burns.

  More specifically, in the embodiment illustrated in FIG. 7, the boiler 50 includes a combustion device 51 including the two-fluid burner 1 and a furnace 52. For example, the boiler 50 uses heavy oil (or light oil, pitch, or the like) as the liquid fuel F as fuel, and uses the heavy oil as steam (or high-pressure air, high-pressure An oil-fired boiler configured to atomize and spray with a gas, a combustible gas, and the like, burn in a furnace 52, and recover heat generated by the combustion.

The furnace 52 is provided so that the combustion space 100 extends in the vertical direction, and a heat transfer tube is provided on a furnace wall 53 that defines the combustion space 100. A combustion device 51 is provided below the furnace wall 53.
The combustion device 51 has a plurality of two-fluid burners (combustion burners) 1 disposed on the furnace wall 53. For example, a plurality of two-fluid burners 1 are provided along the circumferential direction or the vertical direction of the furnace 52. The two-fluid burner 1 includes the burner chip 10 (see FIGS. 1 to 6) according to any of the above-described embodiments.

  Each of the two-fluid burners 1 is supplied with fuel from the fuel supply source 61 through the liquid fuel pipe 3 (see also FIG. 1), and is supplied with steam (spray) from the steam supply source 63 through the spray medium pipe 4 (see also FIG. 1). Medium) is supplied. Further, to each two-fluid burner 1, combustion air heated by exchanging heat with exhaust gas from an air duct 65 is supplied to a wind box 66. Therefore, the two-fluid burner 1 mixes the fuel and the above, atomizes the mixture, and then injects the mixture into the furnace 52 as a mixed fluid, and injects combustion air into the furnace 52 to form a flame in the furnace 52 Can be. The combustion gas generated in the furnace 52 is discharged through a flue 60 connected to the upper part of the furnace 52. The flue 60 is provided with a superheater, a reheater, a economizer, etc. as a heat recovery unit, and recovers heat of the combustion gas.

  According to the boiler, a two-fluid burner capable of reducing dust and NOx is provided, so that a highly reliable boiler can be provided.

  As described above, according to at least some embodiments of the present invention, the liquid film of the liquid fuel formed on the inner wall surface of the ejection hole is uniformly thinned, so that the liquid film is supplied to the upstream side of the ejection hole. The liquid film can be appropriately diffused by the fluid energy of the spray medium, and the atomization of the liquid fuel can be promoted.

  The present invention is not limited to the above-described embodiment, and includes a form in which the above-described embodiment is modified and a form in which these forms are appropriately combined.

For example, expressions representing relative or absolute arrangement such as “in a certain direction”, “along a certain direction”, “parallel”, “orthogonal”, “center”, “concentric” or “coaxial” are strictly described. In addition to such an arrangement, it is also possible to represent a state of being relatively displaced with a tolerance or an angle or a distance at which the same function can be obtained.
For example, expressions such as "identical", "equal", and "homogeneous", which indicate that things are in the same state, not only represent strictly equal states, but also have a tolerance or a difference that provides the same function. An existing state shall also be represented.
For example, the expression representing a shape such as a square shape or a cylindrical shape not only indicates a shape such as a square shape or a cylindrical shape in a strictly geometrical sense, but also an uneven portion or a chamfer within a range where the same effect can be obtained. A shape including a part and the like is also represented.
On the other hand, the expression “comprising”, “including”, or “having” one component is not an exclusive expression that excludes the presence of another component.

DESCRIPTION OF SYMBOLS 1 Two-fluid burner 2 Burner main body 3 Liquid fuel pipe 4 Spray medium pipe 10 Burner chip 11 Chip main body 12 Fuel chamber 13 Fuel inlet 14 Outlet 14a Upstream area 14a1 Upstream end 14b Downstream area 14b1 Downstream end 14e Inner wall surface 16 Medium Supply pipe 16a Outer peripheral surface 16b Tip 17 Medium inlet 19 Medium collecting channel 20 Gap 20a Inlet 50 Boiler 51 Combustion device 52 Furnace 100 Combustion space

Claims (7)

A fuel chamber into which liquid fuel is introduced, and a chip body having at least one ejection hole for spraying the liquid fuel from the fuel chamber;
At least one medium supply pipe for guiding a spray medium to the ejection hole,
With
In the upstream region of the ejection hole, the medium supply pipe is inserted into the ejection hole,
In the upstream region of the ejection hole, a gap communicating with the fuel chamber is formed between the medium supply tube and the ejection hole in a radial direction of the medium supply tube,
When the insertion length of the medium supply pipe into the ejection hole is L, and the size of the gap between the medium supply pipe and the ejection hole is d, the relationship of 5 ≦ L / d ≦ 20 is satisfied. It meets,
The chip body,
A fuel inlet for introducing the liquid fuel into the fuel chamber from the outer peripheral side of the tip body;
A medium inlet for introducing the spray medium into the medium supply pipe from the rear end side of the tip body;
Including
The burner chip , wherein the medium supply pipe extends from a rear end side of the chip body toward the ejection hole in the fuel chamber . A fuel chamber into which liquid fuel is introduced, and a chip body having at least one ejection hole for spraying the liquid fuel from the fuel chamber;
At least one medium supply pipe for guiding a spray medium to the ejection hole,
With
In the upstream region of the ejection hole, the medium supply pipe is inserted into the ejection hole,
In the upstream region of the ejection hole, a gap communicating with the fuel chamber is formed between the medium supply tube and the ejection hole in a radial direction of the medium supply tube,
When the insertion length of the medium supply pipe into the ejection hole is L, and the size of the gap between the medium supply pipe and the ejection hole is d, the relationship of 5 ≦ L / d ≦ 20 is satisfied. It meets,
The chip body has a plurality of the ejection holes respectively provided at different positions in the axial direction of the chip body,
A plurality of the medium supply pipes are respectively inserted into the plurality of ejection holes in the upstream region of the ejection hole,
The plurality of medium supply pipes extend along the axial direction of the chip main body, and are connected to a medium collecting channel for guiding the spray medium to the plurality of medium supply pipes. Burner chip. The medium supply pipe is inserted into the ejection hole only in the upstream region of the ejection hole such that a tip end of the medium supply pipe is located between an upstream end and a downstream end of the ejection hole. ,
In the downstream area of the ejection hole, the liquid fuel supplied from the fuel chamber through the gap and the spray medium supplied from the medium supply pipe are mixed. The burner chip according to claim 1 or 2 , wherein The burner chip according to any one of claims 1 to 3, wherein the gap is an annular gap formed between an inner wall surface of the ejection hole and an outer peripheral surface of the medium supply pipe. The chip body has a plurality of the ejection holes respectively provided at different positions in a circumferential direction of the chip body,
The burner chip according to claim 1, wherein the plurality of medium supply pipes are inserted into the plurality of ejection holes in the upstream region of the ejection hole, respectively. A burner chip according to any one of claims 1 to 5 ,
A burner body configured to hold the burner tip on the tip side, and to supply the liquid fuel and the spray medium toward the burner tip.
A two-fluid burner comprising: A two-fluid burner according to claim 6 ,
A furnace that forms a combustion space in which the liquid fuel injected from the two-fluid burner burns;
A boiler comprising:

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